Treating Wood for Vegetable Gardens

, written by Jeremy Dore gb flag

New raised bed

Wood is a very versatile material for vegetable gardens. Whether it is used to create raised beds, the edges of paths or a frame for protective netting, wood is the natural choice for many gardeners. Apart from being a sustainable resource, it looks good and is great for creating a new structure for vegetable beds that will hold in compost or keep out pests. So when I set out to create a set of long-lasting raised beds for my front garden, wood was my material of choice. Yet, the question of how to keep the wood in good condition is not as simple as it might first appear...

The issue is that all of the common methods of preserving woods have their problems when it comes to growing edible produce. For many of us, one of the primary benefits of growing our own food is the knowledge that our vegetables have not been sprayed, treated or artificially enhanced. Organic principles can be applied very successfully to home gardens but treating the wood in contact with the soil and plants can cause many questionable chemicals to leach into the ground, contaminating the crops. Details of the extent of this problem are hard to come by but the following treatments are commonly questioned:

  • Pressure treated (‘tanalised’) timber: this is where the wood is preserved before you buy it by subjecting it to chemical treatments under pressure, so that as much as possible is absorbed into the wood.  Most fences and posts are treated in this way, to prolong the life of the cheaper softwood used to make them.  The problem is that it is usually very hard to get information about the chemical concoction used in the process, particularly as the wood may have been pressure treated long before it reaches the place you purchase it from. There have been serious concerns about the use of arsenic compounds (CCAs) and heavy metals, particularly when these rub off on hands or get into the food chain.
  • Creosote: The traditional wood treatment for many years, this has now been withdrawn from sale for domestic use within the European Union following advice from organisations such as the International Agency for Research on Cancer who believe it to be carcinogenic. Creosote continues to give off vapours for some time after application and can leech into the soil and groundwater, entering into the food chain.
  • Oil-based preservatives: These penetrate wood very well, giving a deeper protection than many other paint-on preservatives and are the basis of many wood stains. Some are based on vegetable oils. However, they rarely list the ingredients and can contain a wide range of other compounds including fungicides, preservatives, UV blockers and pigments specific to the manufacturer. As a result, it is unclear whether they are safe to use around organic growing areas.
Rhubarb in raised bed

So what can be done to preserve the wood used on vegetable plots? You would imagine that there would be a number of products for the job but there are surprisingly few. The natural alternatives that do exist are often very expensive, not suitable for exposed outdoor areas in contact with soil, or prone to their own problems:

  • Some paint-on wood treatments: which use acypetacs (such as ‘Cuprinol’) are believed to be safer than the above treatments. However, they don’t penetrate as deep into the wood and probably need re-treating more often. Of course, when you have earth permanently against a wood surface, you are not going to be able to re-treat it easily. Most of the products claim to work for years but this is for fences or woods which can dry out, not those exposed to damp soil.
  • Other water-based preservatives: are based on boron salts which are widely considered to be safe to humans and are usually applied as a paint or gel. However, the water-soluble nature of these products means that they don’t chemically bond with the wood and can leach out. These are also harder to find in shops and take a long time to dry.
  • Linseed oil: The classic wood treatment made from natural flax seed, linseed oil has excellent preservative properties and water resistance. However, it is very slow drying and in cold or damp weather it may not even be worth applying it because it can just remain sticky for weeks. As a result many available linseed oils are not pure raw linseed oil but a mixture with solvents such as mineral spirits, often called ‘boiled linseed oil’ to speed up the drying, which makes them much less natural. Even worse, other linseed oils contain many of the ‘nasties’ such as heavy metals used in pressure treated timber. So you have to be very sure you know what you are buying and remember that as a natural material, it doesn’t protect the wood from UV sunlight or mildew. [Also it is very flammable and rags used to apply it have been known to spontaneously combust - beware!]
  • Plant based preservatives: Some vegetable-based natural products are available from specialist companies but they are largely for staining or interior use and tend to be expensive.

 An alternative approach is to choose hardwoods which, unlike the common softwoods  such as pine, will last much longer untreated (up to 20 years) but it is important to check that these are from forestry approved (FSC) sources and there is also the environmental impact to consider of how far they have been transported, coupled with the much higher cost. A better alternative is recycled plastic boards which are long lasting and available from companies such as Link-a-Bord (or Gardener’s Supply Company in the US). Plastic is not usually considered environmentally friendly but this company recycle the uPVC from windows and doors which mustn’t be incinerated or sent to landfill. Because the boards contain an air gap they are good insulators for the soil, helping it warm up more quickly in spring and keeping the plant roots at an even temperature. The cost is predictably higher than for wood but they are good value when you consider their length of life.

Untreated raised bed

Having considered all of these options it seemed that the only wood treatments that are in keeping with my organic principles involved natural products that were going to almost double the cost of the wood required for my raised beds! So, I reached the rather surprising decision that it was best to use untreated wood, using thicker (2 inch) structural grade planks fixed together with galvanised decking screws. That way, although they will still rot, it will be a much slower process and I expect to get at least 5 years from them before I will need to start replacing them. My neighbour is unconvinced, predicting that they ‘won’t last 12 months’. He assured me that the only lasting way to treat wood is with a mixture of engine sump oil and creosote! However, my family is the one eating the vegetables from the beds and I would hate to have this concoction leaching into the fresh produce I feed to my children. If I had to choose an alternative option, it would be the recycled uPVC Link-a-Bords which many gardeners swear by. I was so impressed by the eco-credentials of the company producing these that I intend to use them for other parts of my garden. Ask me in five years time and I’ll tell you if I made the right decision!

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Comments

 
"Just an idea: would it be of much benefit to cover the planks in old plastic bags eg. old growbags etc. using a staple gun? This wouldn't take longer than covering with preservative and I think it might prolong the life of the planks themselves. I haven't tried it myself yet, but I intend too. What are your thoughts on this?"
Dakev on Saturday 31 January 2009
"Dakev, I have thought about covering them with black plastic liner on the inside but I think that through the seasons the plastic would just trap moisture, creating a permanantly damp layer which would rot just the same. Wood has to be able to dry out to prevent rotting and I don't think the plastic would allow this except during hot summers. I also wonder whether chemicals might still leak into the soil below and be taken up by the plant's roots. Thanks for the suggestion though."
Jeremy Dore on Saturday 31 January 2009
"Word on the street is these days the process of making lumber weather resistant is more environmentally sound using a preservative called alkaline copper quat or ACQ. I've also read that studies have shown levels of arsenic leached into the soil and absorbed by plants are minimal. Here's an idea since arsenic will not migrate far: try planting a border of low growing flowers rather than edible crops along the edge of the wood. Lavendar and marigolds bring beneficial insects to the garden and minimize the bad ones. Just my two cents."
Laura on Monday 2 February 2009
"Laura, Thanks for mentioning ACQ. It does sound better than CCAs but is still prohibited in organic gardening standards: see http://attra.ncat.org/attra-pub/lumber.html for details which states: 'Some copper does leach from ACQ-treated lumber, making it unsafe for garden use.' I fully agree with your ideas on using flowers around beds though, particularly if you already have treated timber in your garden."
Jeremy Dore on Tuesday 3 February 2009
"I still use pressure-treated timber, because I have so many raised beds now that replacing them would be very expensive. This material is much safer than it used to be (no more tanalith, which gave tanalised timber its name) but I still would prefer a long-lasting natural alternative. I wonder what effect a wax-based coating would have? Beeswax would surely repel water, extend the life of your timber by some years, and be totally harmless? Is any such product available for external use?"
Paul on Tuesday 3 February 2009
"I use Procol painted timber, its the stuff The Recycle Works use on their compost bins/raised bed kits... so far it has lasted 5 years plus...immersed in active compost! I also have ( not pvc ) recycled plastic beds from Garland.... 5 years on still very good you can buy them from the Organic Gardening Catalogue... hope this is helpful! Compostwoman"
Compostwoman on Tuesday 3 February 2009
"Paul, I, too, would be interested in how beeswax would perform, although I suspect it would need to be combined with other ingredients as I have read that (surprisingly) 'its resistance to water is low but this can be improved by adding a natural resin or oil'. Compostwoman: Procol does look good - a bit expensive which is why I had initially dismissed it - but I hadn't realised you can dilute it to make a much larger amount before application. For any readers interested you can get it from http://www.organiccatalogue.com/catalog/product_info.php?products_id=1675. Thanks for the comments!"
Jeremy Dore on Wednesday 4 February 2009
"one very good option to consider would be Thermawood, this is wood heated to a very high temperature to destroy the cells and drive out moisture. Here at FenceandFix.co.uk we use it for making gates, cladding and raised beds, it looks good as is and takes stains very well.http://www.finnforest.co.uk/default.asp?path=200;256;1317;1318;1324"
simon gibson on Sunday 8 February 2009
"I too am trying to build wooden raised bed and have been told by several saw mills that timber treated with the new tanilith-e is safe and environmentally friendly, with no leaching, no arsenic and is copper based. Have you considered it, or know more about it ? "
Jules on Monday 9 February 2009
"Jules, Tanalith-e is certainly much better than the CCA version, although I am not sure there are any guidelines about whether it meets orgnaic standards, as the copper triazole in it is a biocide used on crops. I'd be interested if anyone has any more information about this."
Jeremy Dore on Monday 9 February 2009
"I investigated wood treatments before buying a new hen house for much the same reasons as I would if I wanted timber for raised beds( I am 100% organic, I eat eggs, I don't want my hens absorbing anything nasty) I found this http://files.recycleworks.co.uk/files/Wood%20preservatives.pdf this http://www.buildingforafuture.co.uk/autumn04/1-23.pdf ( very interesting general read) and this http://www.archchemicals.com/Fed/WOOD/Products/PreservativeProtection/tanalised.htm were most helpful. For the hens, I went for a Tanalith E , FSC house from Flytes of Fancy, My compostbins are FSC wood treated with Procol at Recycleworks. I have had them 6 years now and not re painted them and a few boards at the very bottom (where they are in contact with the ground AND compost all the time) are beginning to go a bit soggy looking....but thats all I have recycled plastic raised beds but IF I were going to use wood, I would go for FSC timber Boron treated if I could afford it, pressure treated/dipped in Procol as an alternative. But thats just my opinion! ;-) "
Compostwoman on Monday 9 February 2009
"Comment trackback from: http://recyclebills.squarespace.com/recycleblog/safe-borders-for-your-vegetable-gardens.html"
RecycleBill on Thursday 12 February 2009
"I am in early days of planning a new 12mx12m vegetable garden - its currently still a daunting pile of rocks and weeds. I had expected wood to be first and best choice environmentally, and while it still might be, the treatment options sound like they are not ! After reading these posts I am thinking more seriously about using recycled plastic for long-term crops eg asparagus but as that may be too high a startup cost for all beds at once I might go for untreated wood for the beds that will rotate annually, then replace with the plastic type one or two beds per year as the wood starts to fail. Hey, that almost sounds like a plan !"
scanda on Monday 2 March 2009
"don't plastics leach bad things too?"
susan hogan on Tuesday 17 March 2009
"what about concrete blocks or bricks for raised beds? burlap rather than plastic? I had a chemical free farmer tell me he was using carpet samples for weed control....imagine the chemicals that would leach from those?"
susan hogan on Tuesday 17 March 2009
"Here's an idea - why use raised beds? No raised bed, no wood - simple. http://simonsallotment.blogspot.com/2009/03/how-i-garden.html"
Simon on Tuesday 17 March 2009
"Susan - I'm not a chemist but the Linkabord people were pretty convincing when I asked them about leeching chemicals. For one thing, I think leeching is mostly a problem with soft plastics and for another, the plastic has been recycled so any leeching should have already occurred in its former life. Also, concrete blocks and bricks sound good but they have one big problem - slugs love living in and around them!"
Jeremy Dore on Tuesday 17 March 2009
"Simon, I agree some people use raised beds just because they are the trend at the moment. However, there are some good reasons to use them if you have waterlogged or heavy soil, a lot of tree roots, or need to add a lot of compost without it spilling onto the paths. So it's not just for no-dig advocates, although I do take your point."
Jeremy Dore on Tuesday 17 March 2009
"Thanks for answering my comment, I agree raised beds have their uses for those reasons, and also tall ones for the disabled, it's just driving me crazy that they have become the "new orthodoxy" everywhere from gardeners world to kitchen garden magazine, without anyone really questioning it and I'd like to see more debate on the subject. btw did you get the chance to read the piece on my blog - I could use some comments! Cheers, Simon"
Simon on Tuesday 17 March 2009
"Simon, a agree raised beds arent needed most of the time - my garden is on old quarry ground, on a slope, so I need the beds to give me a decent depth of soil and walls to keep the soil in. I wouldnt bother if I didnt need to though."
jules on Wednesday 18 March 2009
"I vaguely recall an old organic growing book on my..."
Brian on Thursday 14 May 2009
"Hello I enjoyed reading your post. How about Milk Paint? ( http://www.realmilkpaint.com/products.html )being safe for a vegetable application? Thanx Gene"
Gene on Saturday 25 July 2009
"Gene, Milk paint sounds interesting but I'm not sure it actually adds weather-resistance, although they do have some products that might work such as Tung Oil."
Jeremy Dore on Sunday 26 July 2009
"I have used 3ml and 8ml plastic inside my flower planters and it considerably extends the life of wood pots made from pine or fur. Like to 10 years. I am not sure about using it for vegetbles. what do you all think about using trex. Its expensive but lasts. I don't know about the leaching on it. i love my raised beds, no they are not a fad for me, they let me garden in otherwise terrible doil, they limit the amount of mulch and ammendments I have to use. they decrease labor. They save water. They let the soil microbes and worms do better unlike the old tilling up system. One could do it at ground level and just estblish set walk ways. However, if you have dead solid clay like me that doe snot really work."
rita on Tuesday 30 March 2010
"Hi Rita, I'm not sure about whether trex leaches chemicals. However, when I talked to the Link-a-bord company they assured me that using recycled uPVC like they do does not leach anything because of the specific type of plastic. I think they are a really good investment for heavy clay soils as you say."
Jeremy Dore on Saturday 3 April 2010
"I am making raised beds for my veg garden too and I thought about coating the wood in plain vegetable oil. This way sealing the wood from water and possibly infestation...will this work?"
Rich on Tuesday 6 April 2010
"Hi Rich, Can't remember where I read it but I think vegetable oil would be a poor treatment that will do little for the wood and may even attract unwanted bugs. Although you can use it on surfaces like wooden tables it is a very different matter when the wood is in contact with the soil. Wood breaks down over time where it is damp and fungus gets in - vegetable oil would probably not significantly slow down the fungus which does the damage I think."
Jeremy Dore on Wednesday 7 April 2010
"I started out building timber frames to raised beds on my allotment, then realised I didn't need them. I simply have dug out paths between wide ridges, so that the growing areas are low mounds like the old ridge and furrow system. I actually made the ridges too high to start with, and they still kept their shape. This year i have reduced the height. They work well - not a lot of potato blight, while my neighbours have had terrible yields. I think Bob Flowerdew advocates this method, as timber frames are a lot of work and harbor slugs!"
tony on Friday 16 April 2010
"I'm about to move and build raised beds so I am interested in alternatives. I'm thinking for now I will do what Jeremy does: use 2" pine boards and assume they will rot. For a minute there I was convinced that concrete blocks would be cheap and effective but I had not thought about the slugs! Yep... not good."
Sue on Saturday 24 April 2010
"Tony, raised beds with no frames sounds appealing too... and cheap. But part of what I like about frames is having a place to plant my foot or my butt as I am weeding or tying up plants etc. Maybe an answer is to sink some 4x4s along the sides and put a removable board on top, about 18-24" feet off the ground. Hmm. if I use some sort of removable fastener I could take the rails off for annual re-shaping of the beds. What do y'all think? "
Sue on Saturday 24 April 2010
"Hello all. I am a bit concerned that my first attempt at building a cedar raised bed did not go as well as I wanted. I build a 8'x12' using 1x4 cedar planks and 4"x4" posts (Pine) to reinforce. I did treat the wood with an exterior toner because I was going for of a reddish look with grain of the cedar able to stand out nice. I am now worried that planting vegetables in this bed may not be a good idea? Please help me ease my worries and tell me this will be ok."
steve on Sunday 2 May 2010
"Hi Steve, it all depends what's in that exterior toner - does the can have a number you can contact? I'd say on balance you will probably be OK because it tends to be the pressure treated timber that is worse but you may wish to check with the manufacturer of the preservative. Cedar should be very long-lasting though - a good choice."
Jeremy Dore on Sunday 2 May 2010
"Hi people.. just passing by on my quest for building materials. Here in Australia we have this product... http://www.closetheloop.com.au/ewood/index.htm and the how to .. http://backyardfarmer.com.au/organic-gardening/how-to-build-a-raised-vegetable-garden-bed-out-of-ewood/ From my perspective it is a great choice. non leaching, long lasting and enviro friendly."
John B on Tuesday 11 May 2010
"I have heard that concrete blocks can leach heavy metals like mercury depending on where the sand is from. It is not regulated. Some concrete blocks maybe ok and only leach lime or calcium. Need to research where it all comes from. I heard the southern states have trouble but then everything is shipped all over now. "
Mary Ellen Zeibig on Sunday 22 August 2010
"The solution to all your problems is to build a form to pour concrete planks for the sides of your raised beds. Build the form so the thickness of the planks is 1 1/4". Imbed the concrete with lengths of rebar to add support to the concrete. These will last your lifetime."
JP on Sunday 29 August 2010
"google concrete additives. THere are several chemicals that are added to concrete that can leach into the soil. "
M E Z on Sunday 29 August 2010
"What about using hardiplank/fibrolite type product to line the inside of treated wood. Would there be any nasties in the fibrolite we purchase today unlike years ago when it contained asbestos?"
Cynthia Baker on Monday 30 August 2010
"What I have found in googleing is that hardiplank can grow mold and mildew on it. Might look ugly. Also houses sided with it have a leaching problems of some type. It is made with cement and cement does have additives in it. I have a trek deck and it is suppose to be maintenance free. It grows mold and twice a yr. I have to treat it to prevent the mold and mildew. I am making my beds with hemp fir, 2 inches thick, 2 feet high and sitting on a boarder of brick to reduce ground contact. "
MEZ on Monday 30 August 2010
"I'd like to see more discussion about scortching wood to prevent rotting. In Hawaii, bamboo is scortched for just this purpose. I've never heard of charcoal ever rotting. Anyone with any experience along these lines ?"
hArte on Monday 20 September 2010
"Agreed, it would be interesting to know whether scorching helps, although I'm not convinced it would prevent moisture seeping into the wood below, which could then rot. Bamboo is an altogether different material and very resistant to water (which is why it's used to form flooring for bathrooms)."
Jeremy Dore on Monday 20 September 2010
"Jeremy, Thanks for the feedback ! Never considered the seeping issue. I'm in the process of creating a new garden space and considering the use of fiberglass panels salvaged from a discarded garage door, ripping them to the appropriate width and staking them with rebar. I think this material, whether from garage doors or roofing panels, might be a viable alternative for many gardeners ."
arthur wayne madsen on Monday 20 September 2010
"i live in the gold country of california. the old timers here always scorched their fence posts before placing them, telling me that they'll last much longer. and, believe me, there are some VERY old looking posts about."
maryann Gravitt on Wednesday 15 December 2010
"Regarding concrete with additives. There are additives only if you put them in when mixing the concrete. For making concrete retaining walls for a raised bed, the additives are not necessary. Make a form, add some reinforcing wire like chicken wire and a length or two of 3/8" rebar, and you're good to go. No leaching worries."
JP on Wednesday 15 December 2010
"I have to say my new trex beds did great. I did not want to buy soil to fill the4x12 and the three 4x4's so I put rows of soil every 12 inches and alternated with leaves, grass, pAper, manure, and a little of my clay soil, then covered that with newspaper and planted my vege in between. This fall during cleanup I found it converted to soil. Good job worms!!!!"
Rita on Thursday 16 December 2010
"I have used linseed oil on doug fir to make a large raised bed. It's still holding up after 8-9 years. I do expect it will deterorate eventually but have been pleased with it so far. Our soil is very clayish, too, so the drainage is poor and that should have hurt the raised bed. I found it quite difficult to find raw linseed oil, but did eventually. The data sheet on it lists dryers, but I am 99% sure that in fact the raw linseed oil has no dryers - they just used the same data sheet for it. It does dry very slowly, and you should put 3-4 coats on."
Peter S. on Thursday 6 January 2011
"I must add , I have just ordered and been delivered more recycled plastic rased beds. They are SO versitile and useful and I cannot sing their praises enough."
Compostwoman on Thursday 6 January 2011
"Re scorching. Hi all, when I was a kid, we used half whisky barrels as planters. These were real, recycled whysky barrels, scorched on the inside, rather than imitations found in garden centres. They lasted many many years before falling apart. They were hardwood, so could be scorched to a good depth. I wouldn't bother for the raised beds, unless perhaps you had a small one built of hardwood. RE: ROT- I don't mind! I use untreated S/H scaffold boards and untreated softwood posts, with no plastic backing. It all rots eventually, but can last years before it actually needs replacing, bit by bit; it doesn't matter that it's not eternal. And no contamination! Short of scaffold boards, I use untreated roofing timber or equivalent, as it lasts longer than cheaper softwood. Z "
Zapo on Sunday 6 March 2011
"More about linseed oil...I should have mentioned thay you must use RAW linseed oil, not "boiled". The boiled oil isn't boiled, actually - what that means is that they add metallic driers to speed up the drying process, and we don't want them - they are toxic. But raw linseed oil is just linseed oil. I'm very happy with how this proces has worked for me. As Zapo says, it's not eternal, but I figure 10-15 years of life is pretty good! I don't trust ANY of the treated wood products. Also, to the person with the cedar planters - a lot of cedar is good for ground contact, it's often used for fences and the fenceposts (and is light to boot - nice for gates!) "
Peter S. on Sunday 6 March 2011
"I appreciated reading the comments and experiences. Use of untreated wood is definitely more feasible in a dry climate. My roughly 4"x4" beams had seen 5 years of use in a moderately dry area of South Africa and were still in good condition when I left. The same beams wouldn't make 2 years in southern Louisiana. The positive aspect of untreated wood degrading is that you've just added a bit of of compost. But I do wonder about the possibility of untreated wood drawing unwanted insects."
bill butler on Friday 11 March 2011
"hello,we have used a product called Eco Wood Treatment,on our raised beds,it has worked very well . its all non -toxic.the web site is www.ecowoodtreatment.com , we would highly recomend this to the gardeners out there,sincerly carol baker west virgina"
carol baker on Saturday 12 March 2011
"hi we used a product called eco wood treatment on our garden boards ,its all non toxic , home depot had it,I understand it is also at some sherwin williams stores.great product"
barry on Friday 8 April 2011
"Barry, where did you find Eco Wood Treatment? I've called Home Depot, Lowes, Ace, True Value, etc. No one has it. Sounds awesome, just can't find it. Help"
Robin on Sunday 10 April 2011
"I know I've come late to the party, but you need to change the soil in a raised garden bed, along the lines of fallow ground and the currently planted ground idea of farming. The wood SHOULD rot since it's a natural thing. Beds need to be worked and having the would rot out makes it occur at a natural time. I've used pople/poplar/aspen (softwood) planks from my father's pallet shop, which are untreated and they've lasted four years in Michigan weather--that's snow and ice and rain and heat, depending on the year. There's work to make the gardens, but having something that you confidently put in the compost sans nails or screws is comforting to me. If anyone's interested, another forum talked about this issue, and here's a recipe from it: http://mailman.cloudnet.com/pipermail/compost/2003-February/010315.html This was developed by the USDA Forest Products Laboratory: 1 ounce of paraffin wax 1 gallon less 1 2/3 cups of turpentine 1 1/2 cups of boiled linseed oil (this is refined linseed oil as compared to raw linseed oil) See the link for the rest of the recipe. For all our talk of being green, we seem to miss one of the most important points: If we want to be natural gardeners, we have to take the rot with the renewal, don't we?"
B on Tuesday 12 April 2011
"I agree, wood should be expected to rot naturally - taking the rot with the renewal is very true. Two years after writing this article my thick (2") untreated raised beds described in this article are doing wonderfully and look like they'll keep going for many more years. I'd really advise against that concoction from the USDA Forest Producst Laboratory though - boiled linseed often contains nasty heavy metals and terpentine and parafin shouldn't be used near vegetables. The person who posted it claims it came from an organic vegetable gardening book which seems hard to believe - even in 1994 when the book was published they should have known how harmful these things can be!"
Jeremy Dore on Tuesday 12 April 2011
"I just spoke with the folks at ecowoodtreatment.com and it sounds like a great product. after much consideration i figured that using fir framing lumber (2 x 12") is the most cost effective- i just got enough lumber for 2 12' x 4' beds for under $70 US. When it rots i will replace it or go over it. Good quality cedar or locust that would really last would cost a ridiculous amount in comparison. "
Jon A on Tuesday 12 April 2011
"I absolutely agree with Jeremy Dore - the USDA Forest Products finsih should not be used in gardens! In their defense, they never suggest that it should be - rather their article suggests it for decks, fences and the like, but doesn't mention raised beds (and containsa warning that some of the materials are toxic). The srticle is here: http://www.woodweb.com/knowledge_base/fpl_pdfs/fplrn046.pdf However, please DO consider using RAW linseed oil, on its own. It takes a long time to dry, and you need to take care with the rags to gaurd against spontaneous combustion, but as per my several entries above I have found it to work quite well."
Peter S on Tuesday 12 April 2011
"The Sherwin Williams on Beltline in Richardson is starting to carry Eco Wood Treatment. They plan to have it in stock by this weekend."
robin on Tuesday 12 April 2011
"We have built our raised beds (redwood) in our fro..."
Jenn on Wednesday 13 April 2011
"hi to robin we bought our eco wood treatment from sherwin-williams great store!"
barry on Friday 15 April 2011
"Just talked to the guys at Timber Ox Green. I am ..."
Jenn on Wednesday 20 April 2011
"hi, bought creosote from b and q last month (06/11)"
tim negus on Wednesday 29 June 2011
"What about painting the boards with asphalt emulsion?"
Greg Kabanuk on Tuesday 9 August 2011
"Creosote is still on sale I have bought some recently and I also saw it in b and q yesterday 8/8/11."
Tim on Tuesday 9 August 2011
"I don't think asphalt emulsion is a safe for vegetable gardens as it contains a large proportion of asphalt mixed with unspecified chemicals to make it easier to mix and spread. Generally petrolium products should be avoided in edible gardens."
Jeremy Dore on Wednesday 10 August 2011
"I used untreated recycled scaffold boards to edge my garden beds, on the basis that they would last 3-4 years and then be replaced. In that time I may want to re-style the garden anyway. I also considered using used roofing slates to create beds, but couldn't source any in the right time frame - but have seen them used successfully locally."
Trish Brady on Friday 12 August 2011
"I'm pretty excited about using recycled fiberglass garage door panels for my raised beds. I've staked them with rebar every couple of feet. They're rot proof, free, light in weight, and the perfect height for bed making (can be easily cut and fastened together for length and corners ). I would guess they could also be painted if one were so inclined. "
hArte on Friday 12 August 2011
"I would absolutely not use creosote, which is toxic, for anything you are growing vegetables in. Or for any planter box, for that matter, as you never know what the person after you wil use the boc for."
Peter on Friday 12 August 2011
"I recently discovered a lovely place in Attleboro, MA called the Seven Arrows Herb Farm. It's 4-acres of pure heaven. While strolling around the outside nursery area which houses many raised beds, I was puzzled by the wood being used. It looked rough hewed and I could not identify what kind of wood it was. In talking to Michel, one of the co-owners, I learned that the wood was pine and came from a local sawmill. It is completely undried and untreated, just the way it is sawed off the log. As raw wood, it retains all the natural pitches and resins of the tree and is very resistant to rot. Miche tells me that some of the beds in the nurseary are going on 25-years old and other than the color change from natural weathering, they look like they are nearly new. When I need to replace the wood in my raised beds, I will be getting it from the nearby sawmill. I was quoted a price of $6-8.00(USD) for a 10 ft. 1 x 10 board. My kind of prices! "
Susan Baar on Sunday 14 August 2011
"Harrod sell a raised bed kit the wood has been high pressure treated with safe timber preservative which was selected in consultation with ‘Garden Organic’ - this has to be okay doesn't it?"
George on Friday 19 August 2011
"My raised beds are actually HDPE playground borders that stack and interlock at the corners or anywhere with large steel pins and come in sections one foot by six feet and will stack to two or three times that. I have every reason to believe they will outlast my grandchildren."
Greg Kabanuk on Friday 19 August 2011
"Tim mentioned: 'Creosote is still on sale I have bought some recently and I also saw it in b and q yesterday 8/8/11.' I bet ya didn't - it's called 'Creocote' and has had the real nasty carcinogenic ingredients removed. I would want to vouch for the rest of the ingredients though!"
cswd on Friday 30 September 2011
"Hello all. Very interesting information on this subject. Two years ago we built a raised bed on part of our patio as we were so short of space to grow vegetables. Wood from various sources including some removed from our roof when we had a loft conversion was used. As I was unsure of the history of all of the various pieces of wood, which may have had some nasty treatments put in or on them in the past, I used a double layer of black polythene DPM 500 gauge, as used under concrete floors, to line the sides and bottom of the bed. I put numerous drainage holes in the bottom layer so that any excess water will escape. Am I now in trouble with chemicals from the polythene being a potential problem? I would be grateful for any help and comments from all of the experts out there. Many thanks. Michael "
Michael Clare on Saturday 22 October 2011
"the only product we know of thats safe for raised garden beds is called ECO WOOD TREATMENT,, we found it at sherwin -williams but its at most garden centres,as well home depot has it ,carol newstead"
carol newstead on Thursday 27 October 2011
"hi. im looking into building half a dozen raised garden beds, i have around 50 metres of second hand oregon timber, painted inside and out. my questions are is the oregon suitable and will it be a problem that the inside will be painted? thanks"
larry on Saturday 5 November 2011
"i am currently building a 30"raised veg garden . was asked not to use pressure treated on it . to get additional life out of the untreated 2x10 pine boards i am using aluminum coil stock as a lining and will probably coat the wood first with linseed oil as well . the coil stock comes 2' x 50' sold and hardware stores . does anyone have info that aluminum can break down and leach into the composted soil. ?"
steve woods on Tuesday 29 November 2011
"Regarding Steve's consideration of using aluminum as a veggie bed liner: naturally occuring aluminum is widespread and not notably toxic. However in our industrialized society we are all frequently and repeatedly exposed to various concentrations from numerous unnatural sources and hence there should be some concern about the cumulative effects. Aluminum toxicity has been at least tentatively linked to a variety of neurological and skeletal disorders. So will the exposure to aluminum just from the liners be enough to cause any problems? Probably not. Can it cause problems when added on top of all the other aluminum your body absorbs? Possibly."
bill butler on Tuesday 29 November 2011
"We are a Log Building Company based on the West Coast of Scotland. We treat all our logs with 100% natural mixture of pure raw linseed oil, gum turpentine, beeswax and carnauba wax. There are no added metal driers or other manmade unatural additives. If we add pigments, then we only use 100% natural earth pigments. A totally non toxic environmentally friendly mix for the preservation of timber. If anyone is interested, you can view our contact details on our website www.tsarina-imperial-dacha.com"
Michael Dutton on Friday 2 December 2011
"What about old fashioned white wash? Would it be considered organic ? $ "
Vern on Monday 12 December 2011
"@ bill butler Re: steve woods/aluminum... from what I recall about cooking in aluminum the worry comes in when aluminum comes in contact with acids. Though I steer clear of cooking in aluminum at all, unless one's soil is very acidic I would think the aluminum would not leach. Just my humble opinion though... nothing scientific."
Cinny E on Saturday 17 December 2011
"I am looking for an alternative myself and here is what I have found do far: 1. RECOCHEM is in the wood preserving and chemical business, their product "Clear Wood Preservative" http://www.recochem.com/en/products/wood_preservatives/clear_wood_preservative/item/clear_wood_preservative/ states that it can be used in horticultural applications, however the director Robin LeSage - Compliance and Technical Information Manager for RECOCHEM stated to me, "...thank you for your question. Unfortunately it is not recommended for food vegetable or fruits". Therefore, I would not recommend this product for food applications, however for non-edible plants, this seems to be a good solution. 2. Next is a product called "ECO Wood Treatment" found at stores such as: Home Depot, Lowes, Rona, Ace etc., and online directly from their website. http://www.ecowoodtreatment.com/index.html I have not contacted this company, however their website makes a clear argument that their product would be safe for a food crop application. Their product is not premixed, but, the benefit is that you only mix the amount you need for the project and store the dry product for a later use. I do not have any information on the durability and rot resistance for our garden bed applications at this time. 3. Exterior latex primer and paint(applied separately). There are low VOC products which may be classified as non-toxic. I feel this may be an acceptable solution and decorative as well, but to purchase and apply a primer (I feel separate steps would be justified in this application) and paint I am not sure of the overall benefit at this time. I am looking at the latex rather than the alkyd paint for a healthier option, and latex paint does "breathe vapour" whereas alkyd does not. If someone else has any further information, please feel free to add on. "
Craig Steinmann on Wednesday 8 February 2012
"finished the project dec , the raised garden bed, went with the aluminum lining on stock 2x pine, it seemed to be a cost effective and quickway to protect the untreated lumber and capped it with a 1x4 cedar top to keep/reduce water and dirt from getting between the coil stock and lumber. used just enough alum roofing nails to keep it place then drainage peagravel, landscape cloth , and a two feet of pogo's leafgrow/vegetable soil from olney. id do it again that way. i might add dupont tyvek building wrap as an additional first layer for the next time. enjoy"
stevewoods md. on Wednesday 8 February 2012
"Advice please ? I am looking forward to starting an organic veggie patch this March and the more I read the more I become concerned about nasty toxins in my garden soil. Can the(creosote?)treated railway sleepers that have been standing in my neighbours garden for at least 25 years, about 2-4 metres slightly uphill from the most suitable veg planting location in my small 10x10 metre garden pose any kind of health threat? They have about 12 sleepers around a raised flower bed, and further down their garden another 4 or so. There is a brick wall with shallow foundations in between... My cheapest alternative option is to use some grow bags along the wall and make one raised bed from four thick oak planks that were once furniture shelves in the house. These were originally untreated or perhaps just lightly oiled?,then varnished and stained about 23 years ago..should I sand them down or leave them as they are...will that help, as the dust will blow all over my garden anyway :( !! I have no idea what product was used on the planks back then. Is a bed just 30 cms deep/high filled with fresh clean soil etc going to be enough to get above any contaminated soil, I will lay down some anti weed plastic sheeting underneath (not so sure about the plastics leaching from that either)? Cheers."
JayneH on Tuesday 21 February 2012
"To all above, Toxins,Toxins everywhere and not a drop to drink. Todays health hazard is tomorrows cure, like eggs and butter. So we cannot turn into Howard Hughs, but must be aware and make the best of what we can. My family has eaten vegitables out of a raised bed garden out of railroad ties for twenty years and are as healthy as can be expected, no cancer! But we now have a certified Organic farm and would not think of using them again! If you are concerned about the soil, do a raised bed, build your own soil from composted leaves and grass clippings from a contolled enviornment. That is from land not modified with petroleum based fertilizer,herbasides,pesticides,fungasides. Toxins leach down not up. What you add to the top of your raised bed will soon end up at the bottom. So add what you can afford and are comfortable with. The question is how green do you want to be or can afford, light green,medium green or dark green. Each is attainable with greater cost. But most important what ever you grow in your back yard will be more healthy than what you buy at Wall Mart. I now use rough cut 2"x6" cedar planks two high bolted together with steel bracing and replace when needed, about 5 to 7 years. The richer the soil the faster the decay. Those oak planks are to valuable to use and will be compost in two tears. "
Vernagain on Tuesday 21 February 2012
"@Vernagain, thank you for your response, I appreciate your good sensible down to earth (is there a pun in that?)advice. I am going to do what I can with the resources available and forget the rest so I enjoy my new hobby and hopefully...the (medium green) organic fruit and veggies of my labours :)"
JayneH on Wednesday 22 February 2012
"Re Scortching the wood (20th Sept 2010): the scortched bit lasts millenia - scortched sharpened ends of poles have been found when excavating 2000yr old Roman small forts of the type erected for brief encampments. The soldiers would carry poles so they could put up an overnight defence quickly. Yes the insides would rot, but I guess much more slowly as bugs wouldn't get in via the scortched end. RW"
R Wilson on Saturday 25 February 2012
"Very good discussion and timely for me since I am replacing my 14 year old raised beds. They were made in part of cedar and the rest pine due to cost and have lasted all this time untreated. After MUCH research I am pretty sure I am going with thick pine boards to build three 10' x 3' beds and put the boards on a thin bed of gravel to help keep them from lying on moisture. Secondly, I will try the ECOWOOD treatment though I would like to know the ingredients and not just take the company's word for it being safe. For posts to attach the long boards to, I will probably use cedar timbers I will cut to size (probably 18 inches). I'll put them at the corners and in the middle of the long boards, attached using glavanized screws. I would strongly like to discourage anyone from using pressure treated lumber or creosote or anything like that. Not good for your veges, you, your kids, pets, other critters or the environment. My early years I tried unframed raised beds and it was a mess and not worth the trouble. Plants were too easily disturbed and it didn't work well with weed mats or row covers. (two things I also highly recommend)."
JP on Saturday 10 March 2012
"JP; You might consider driving 24" x 1" raw angle iron inside the corners with carriage bolts and on the inside or outside of the long runs. Rust only puts iron into the soil and will be their for several wood applications."
vernagain on Monday 12 March 2012
"I just noticed there was another JP on this forum (or more than one?) so I am changing my name to John Paul. I am the JP who commented on March 10, 2012. Thanks for the suggestion vernagain. That could work in place of the cedar timbers in the middle on the long runs and save some money in the process. I want to still use the cedar posts on the corners since they act as a way to join the boards as well as improve stability. "
John Paul on Tuesday 13 March 2012
"i have not been to thius site since you started talking about eco wood treatment. i have used it. IT REALLY IS HARD TO FIND IN CALIFORNIA, which is where i am. i went directly to eco wood treatment. it's canadian. salt spring island, bc. i called sherwin williams, home depot,etc. no help. just go to http://ecowoodtreatment.com/ or ecowoodtreatment@yahoo.com. i have not had enough time elapse to know how long it works other than what the company tells us. but it's the best thing i have found so far."
Maryann Gravitt on Tuesday 13 March 2012
"You know, I've been thinking that where I live businesses are always offering free pallets. I might just make a frame from angle iron that I could put easily replaceable pallet wood into."
Greg Kabanuk on Tuesday 13 March 2012
"I've hit upon an idea to share and maybe others could help develop. Raised bed perimeter material made from corrugated metal roofing (new and/or recycled ). I'm imagining cutting the roofing width wise to approximately 4" more than the depth at which the bed wants to be. The resulting panels would then be interlocked end to end and buried that additional 4" below grade. Every 2' - 2.5' a stake would be driven (rebar, cedar , electrical conduit cut to length )on the outside . The roofing could be free formed to most any shaped bed desired ! Any ideas on how or what to put on the uppermost cut edge of the roofing strips to make it a little more friendly to plants and gardener ? "
hArte on Wednesday 14 March 2012
"To Greg K: I am not sure that rough wood used for pallets would be very durable. Maybe, just not sure. Also its not very wide usually so your raised beds would be shallow unless you find a way to stack them. To hArte: that metal roofing might work but I wonder what the cost is? Its a very good idea I think otherwise with the only hassle being the cutting of it. That might not be so easy. How were you planning to do that? Regarding EcoWood - I just ordered some thru Home Depot and it was not problem at all. It was $16.49 base price for a gallon with the whole thing coming to nearly $25 with shipping and tax. Its also newly offered thru the Gardeners Supply catalog (gardeners.com) but it was $3 more. "
John Paul on Wednesday 14 March 2012
"I'm still working on the design, but I was thinking of a top and bottom angle iron like a bed frame rail horizontally top and bottom and the pallet wood, which is in standard lengths already, inserted vertically, like barrel staves. They could easily be replaced when they rotted. If anyting, this might be too high for some people or some places, but where I live, the soil is nothing but beach sand, so anything but a raised bed holds no nutrients or water."
Greg Kabanuk on Wednesday 14 March 2012
"john, where are you that home depot offers it? i did see it in the gardeners supply catalog. what i purchased was in powdered form, which i mixed with water. the fact that it is now more available is certainly a good sign."
Maryann Gravitt on Wednesday 14 March 2012
"Greg: I can see how a rail could work well for the frames and you do have the advantage of the pallet wood being free so I say go for it! Maryann: I live in Minnesota and I just ordered it online. Just go to homedepot.com and search for eco wood. It is in powdered form and, from what I read, you just mix the amount you think you need at the time. I like that since you are much less likely to waste any. Mine should arrive in 5 days. Don't know how soon I will complete my raised beds but I hope to come back and report on the whole process. "
John Paul on Thursday 15 March 2012
"has anyone considered using a wax coating"
phil on Tuesday 27 March 2012
"I've recently built planters out of a combination of pine and pressure-treated wood that I plan to grow herbs in. I'm thinking about lining the inside of the planter with sheet metal. Are there any health concerns I should take into consideration before taking the sheet metal route? "
Ryan on Monday 9 April 2012
"I am thinking about using Lime for my raised beds - has anyone ver used it on wood? Much thanks for any input."
Francoise Murat on Wednesday 11 April 2012
"We made treated lumber vegetable planters for our deck. Didn't think about the danger of the chemicals before hand. Haven't put soil in the planters yet. I'm thinking that we should line the inside with a heavy duty poly before adding soil. Any thoughts or suggestions?"
JL on Thursday 19 April 2012
"We made treated lumber vegetable planters for our deck. Didn't think about the danger of the chemicals before hand. Haven't put soil in the planters yet. I'm thinking that we should line the inside with a heavy duty poly before adding soil. Any thoughts or suggestions?"
JL on Thursday 19 April 2012
"What about making the bed frames with cement bags, chicken wire and then stucco? Anyone has ideas about this?"
Dania on Thursday 19 April 2012
"I wanted to report back and say things are going well with my raised bed project. Its a lot of work because I am replacing already existing beds which means a lot of dirt moving. I did apply the Eco Wood treatment and had just enough of it to cover all the boards and posts. (using the smaller 1 gal. size). It was easy to use and covered pretty uniformly with a few darker spots. You just brush it on and its very thin so you have to be careful about splashing. It left a few brown spots on my garage floor but they seem to be fading. Never found out whats in it - there was no list of ingredients or chemicals which I think should be available but its touted as very safe. I ended up using 10' x 2" boards (actual width 1 1/2") that are 11 1/4 " high - the minimum height I wanted for the beds. Those were for the lenght and for the width I bought 12' boards with the same dimensions which I cut to make three 3' boards for so that each bed is 10' x 3'. It turned out I was able to get fir boards instead of pine with the former being a bit harder wood than pine. And I used red cedar timbers for the posts - actual width 3 1/2" on all sides and I cut them to approximate 16 foot lengths leaving about 5 1/2 inches protruding beyond the bottom frame of the beds. This is the part you stick in the holes you make in the ground so the bed is stable. Essentially I used the plan found here: http://www.sunset.com/garden/backyard-projects/ultimate-raised-bed-how-to-00400000011938/ It was the best plan I found online for the do-it-yourselfer. I am not doing everything they mention, such as the pvc pipe and my dimensions are different and I used the eco wood treatment but that is the basis for what I am doing and my beds look very similar. I think its a nice look. I have one bed in place and that went well. I am creating pathways nearly 2 feet wide between the beds and I have two more to put in place. After everything is done, I plan to put up a decorative fence around the whole thing. Oh, I also used 4 1/2 inch decking screws which were good to work with - they said they didn't require predrilling but I went ahead and did that anyway - other sites recommended it strongly. I'd say they were a little long and 4 inch screws would have been fine. I also didn't use the hardware cloth but I have had little problem with moles, voles and such. The Sunset article cites wood screws but I would recommend the deck screws - easier to work with, go in more smoothly and probably hold better too. And they say 3 1/2 inch but I would go with 4. Anyway, so far, the whole process is going well and I'm glad I opted for this method. The beds seem strong and they look good and I think the size will work out well. "
John Paul on Friday 20 April 2012
"I'm using redwood for my raised planters.. but one..."
Dubl- A on Friday 4 May 2012
"To Dubl-A: I actually mentioned that on March 10 (as JP then) but didn't follow thru with the gravel or rock simply because the whole project was getting to be so laborious and I decided to leave out that step and rely on the Eco wood treatment alone for protection. However, I do think it is an excellent idea and would definitely help. Also, a correction from my post of April 20: in the middle I wrote 16 foot lengths but I meant I cut the posts to 16 inch lengths. I have been planting away in my 3 new raised beds and, so far, I am very happy with them. The deck screws I mentioned above are the brand Spax and are also called lag screws for exterior and treated wood and they have an integrated washer T30 head so you need that type of drill bit to drive them in. I highly recommend them. "
John Paul on Saturday 5 May 2012
"Does anyone had any experience or info on a product called Lifetime Wood Treatment? "
Dania on Saturday 5 May 2012
"Not sure what I'm going to do for treatment of exterior, but planning for untreated 2x6 and likely going to staple landscape cloth to the insides. Covering the top with 2x4 on flat for rail. I figure the cloth will retard the rot process on the inside but isn't plastic/toxic and can breathe."
Scott on Saturday 5 May 2012
"Scott: what brand / model of landscape cloth are y..."
Dubl-A on Monday 7 May 2012
"Last year we made a raised planter for our vegetables. We have a dog and so didn't want to plant anything in the soil. So, i've just come in from getting preparing the soil and the area so I can begin planting tomorrow. Problem: the box made from leftover construction wood appears to have what could be black mold on it in some places. I'm fairly certain but please confirm that I need to toss out everything and start over - the dirt - the box - everything - right?"
Meada on Sunday 20 May 2012
"For the best results, just use cedar boards, they are rot resistant, and will last for years. The extra few dollars you will spend is well worth it, and you don't have to worry about any chemicals leeching out, or have a need to treat the wood. I used cedar for my 4' x 20' raised garden, and couldn't be happier. The cedar boards also look quite nice."
Dan on Tuesday 26 June 2012
"Cedar is a great way to go but you need thick boards for durability and, if you are building large beds or more than one, it can get very expensive. And even Cedar doesn't last forever. I strongly suspect my fir boards with the eco wood treatment will last as long or longer based on my experience with a compost bin made of cedar. But, either one will work well. Its just that, based on value, I think fir or pine with a "safe" wood treatment, has a slight edge. I did use cedar timbers for the posts the boards attach to however. Mainly I did that based on the idea that they are actually partially buried in the ground. However, I also treated them. So far my beds are proving to be excellent and my vege garden is thriving. "
John Paul on Tuesday 26 June 2012
"Thanks for the feedback. We're using untreated douglas fir. I paid attention to some of the other entries and lined it with cardboard and newspaper. So far drainage is good and the plants are thriving. I greatly appreciate this blog. Now all I have to do is keep the pest out. Last year the tomatoes and corn were infested with very small black bettles. Nasty looking as they would group together and look like a black moss. I've so far sprayed all of the plants with a little dawn and water mix. If anyone has suggestions for a good natural pesticide I'd appreciate a follow-up. Thanks again."
Meada on Tuesday 26 June 2012
"Seems like the raw untreated wood from the sawmill would be the healthiest. I would not want to eat plants placed in treated wood boxes....painted with plastic. I would not want duponts Teflon sheets....tyvec placed anywhere around my garden let alone wrapped around my house. Metal also seems like a very bad idea. I even worry about what chemicals are coming out of my hose to water the plants. "
Susan on Wednesday 27 June 2012
"use concrete blocks and buy sluggo"
roy willmond on Sunday 15 July 2012
"Timbersil... non-toxic, 40 year guarantee, wood infused with ordinary glass... http://www.woodwontburn.com/non-toxic_lumber_california/product_information_glasswood.html Here is a link to the main company (they list some distributors) http://www.timbersilwood.com/ I saw an episode of "this old house" where they built a raised bed for a guy in a wheel chair... It was pretty cool... But the coolest part was the wood... It's been infused with glass which makes the southern yellow pine they start with, as hard and structurally sound as hickory... Bugs won't eat it, it very fire and rot resistant as well as mold and fungi resistant... It takes a stain as well as paint or you can leave it natural and beautiful. People are using it for a lot of projects, and while it is awesome for fire protection, it seems to be really popular with applications where wood contacts moist soil (planter beds)... It doesn't leech anything into the soil and the glass is simply silicon... You can order it and have it shipped to any job site. And is a winner in my book. (note, I do not work for them, I am just an organic gardner)... I don't like the plastic decking as I don't believe what they say about how it doesn't leach. It is recycled plastic with a lot of PVC in it... PVC is loaded with BPA as well as other toxins. All plastic leaches to some degree, and I'm not about to grow plants in wet soil, baking in the sun surrounded in toxin leaching plastic (sun and moisture make plastic leach more). Concrete is not a good solution as it would alkalize the soil too much and it would be a pain to balance. Yes that can be done organically, but it would never be right... Besides, concrete cracks, breaks, and crumbles and I am looking for something that would forgive an occasional ding from the mini-rototiller. I could see doing brick, and I'm sure that would look incredible, but I think it might be far too expensive and wouldn't forgive an occasional knick from a mini-rototiller when it comes time to blend in some fresh organic compost. If I hadn't found timbersil, then I would have gone with a bare redwood, if I could get it at a decent price (on sale), or some untreated 4x4s of doug fir that I might only get 3 to 5 years from. As far as treating regular wood with anything prior to building a planter bed out of it... As they say in NY... Fuhget about it... It's not worth the time and I wouldn't risk getting anything nasty in my vege gardens. "
Paul on Monday 23 July 2012
"That Timbersil sounds great. I just wonder about the price and how to actually obtain it. I didn't see many dealers on their site and none near me. You don't say if you actually used it yet or what project you are building. Did you just order it thru their main website and how much was it? You made some excellent points about other possible material choices and I agree. What I did with the fir lumber and cedar posts with the Eco Wood treatment has worked out very well but for future projects, the Timbersil might be a wise choice, depending on cost. Redwood would be wonderful but the cost is almost prohibitive I have found."
John Paul on Monday 23 July 2012
"We just cut down 6 x 100' Northern White Pine in upstate NY and are going to mill them to use on the property here. I want to mill some to make raised beds, and it sounds as if the consensus here is to cut them thick. My original plan was 1" but maybe I'll do 2". I still plan on letting them dry though, I might lose some pitch and resin but they'll bend less. I don't want to line them with plastic, between melting snow and the rain here, I might end up with sodden beds if I'm using plastic. Plus, I'm trying to do this the easiest possible way. That said, I think I may look for the eco wood treatment unless someone has another recommendation. Any suggestions for helping pine weather raised bed conditions most appreciated!"
Daniel on Sunday 5 August 2012
"Definitely go thicker with the pine. Its also advised to make the height of the frames at least 10 inches. Mine are 11 1/2. I used the Eco Wood Treatment (that is the actual name). I never found out what is in it however. I did read something on another garden blog that it is made up of minerals. I believe its made in Canada. I bought it thru Home Depot and I saw its also available thru Gardener's Supply Co. $19.95 to treat 150 square feet. I made 4 10' X 3' raised beds and it was just enough to treat all of them. They also offer a larger size to treat 750 sq. ft. Here is what they say on their ecowoodtreatment website: It has been tested by Independent Laboratory Testing to determine there are no harmful substances to the environment, including air, water, soil, and plants/trees. It contains no solvents and no chemicals. The natural weathering process results in high UV protection. Eco Wood Treatment is safe to use around children and in playgrounds / play areas. ECO WOOD TREATMENT is a non toxic wood preservative." I think its smart not to line the beds with plastic - it and possibly other liners would just trap moisture and encourage rot I believe. I would also recommend going to sunset.com and searching for "ultimate raised bed" and use that as a starting point. It worked well for me. "
John Paul on Sunday 5 August 2012
"Thanks John, my sister made beautiful raised beds based on that Sunset plan! Eco Wood doesn't tell you what's in their products. I imagine it would have to be on the label, I just purchased some Sikken Cetol SRD to treat a cedar deck and in small print it's listed there. So these things aren't completely proprietary, they have to acknowledge something. Interestingly, mineral oil, vaseline, mineral spirits are all petrochemicals that can be called "minerals" - since they came from the ground. It doesn't make any sense that you could crush up some limestone or feldspar, mix it in water, and it would soak into and protect the wood (though maybe it does!) So there has to be something besides minerals. Anyway, I think I'm going to have the wood cut to 2" or even 2.5", and maybe instead of 10" I'll go with 11 or 12. And I'll probably try the eco wood treatment, it sounds like the best thing going. By they way, it's made in Salt Spring Island, which is one of the most beautiful places I've seen!"
Daniel on Sunday 5 August 2012
"The irony is that the new ACQ treated lumber is made with copper. But, so is Bordeaux Mixture. However, Bordeaux mixture is accepted by organic certification boards and widely used by organic gardeners and farmers, but ACQ is banned? So, the situation now is that one can spray a crop with huge amounts of copper that are totally soluble, readily leachable and freely available to the plants (and still keep to "organic" standards), but can't plant in a raised bed using wood where the copper is bound to the wood. Doesn't seem very logical to me. If one wants to practice organic methods, maybe the thing to do is use the last bits of old growth Yellow Cedar and treat it with Bordeaux mixture (or use Chinese made plastic wood as everyone knows they have incredibly high environmental standards). Maybe it's time some of the organic certification people updated the standards to reflect modern conditions. Copper may be somewhat of an issue, but in a garden bed I'd be more worried about what's used in the plastics in the irrigation lines, the plastics in commonly used "mulch" fabrics like Remay, the lead (and copper) in common plumbing fixtures or whatever chemicals the plastic lumber may be leaching into the soil - none of which are regulated (or even seem to be on most people's radar). "
mark on Tuesday 11 September 2012
"Hard plastics are relatively inert when not exposed to UV Rays, heat, or strong chemical extremes (acid or base.) If there's a chemist out there, please correct me if I'm wrong. In garden conditions, such plastic isn't likely to leach much. And - while I'm not a chemist - there most definitely are different forms of copper. Copper pipe or tape to keep down snails isn't going to poison you, but ACQ will. Saying they are the same is like saying table salt and hydrochloric acid both contain chlorine so table salt will cause 3rd degree burns if you put it in your mouth. Whatever this bordeaux mixture is, it would be better to find out as much as possible about its exact chemical properties before assuming it has the same problems as ACQ."
Daniel on Tuesday 11 September 2012
"Any reason why nobody has recommended pure tung oil yet? The pure stuff is 100% from the tung plant and has excellent wood preservative properties. This is the same stuff some folks use to finish wooden salad bowls and tongs. Historically tung oil was used on the wooden sailing vessels in China."
adam on Sunday 16 September 2012
"Tung oil is a very interesting suggestion and worth investigating."
John Paul on Sunday 16 September 2012
"I don't yet know how well it will weather, but I just built my raised beds with wood coated in mineral oil. Unlike vegetable oil it does not attract pests, however it is food-safe. It is used in industry to lubricate machines that handle food as well as to treat wooden kitchen utensils. I bought mine in a pharmacy, it's in the laxative section. Not sure how it measures up to organics "standards" but it has a long history of human consumption so by my personal standards this is sufficient."
Sara on Wednesday 31 October 2012
"I have untreated raised timber beds that have lasted 4 years now and looking good. However, in the interim, i have added galvanised iron raised beds, and i'm a convert. They are much deeper and hence retain moisture better - I am watering my wooden lower beds much more frequently. Make sure you buy ones without AQUAPLATE lining, which is a plastic lining that is applied for drinking water tanks. I can't see that there is anything toxic in galvanised iron, and you can ask your supplier to use a solder that doesn't contain zinc."
katie on Friday 7 December 2012
"oops, solder that doens't contain lead."
katie on Friday 7 December 2012
"I am so happy with the beds I've created with recycled fiberglass garage door panels. Each panel was cut length - wise with a skil saw , corners bolted together using the aluminum channel that the panels were framed in, and metal rods (pipes) driven into the earth every couple feet around the perimeter for a little extra support. They're werkin' great !"
hArte on Saturday 8 December 2012
"I am interested to build raised, movable beds and i wonder if my used cooking oil from the deep fryer would work if applied with brush while still warm. Any thoughts? "
Bradley on Saturday 2 February 2013
"No, it wouldn't work. It doesn't have the preservative properties required."
John Paul on Saturday 2 February 2013
"Hi,i WAN TO START ON A VEGETABLE GARDEN FOR BUSINESS PURPOSES BUT LACKS THE REQUIRED EXPERTISE. I ONLY WORKED AS A GARDEN LABOURER FOR TWO YEARS AND SAW THW NEED AND OPPORTUNITY TO VENTURE IN THIS TYPE OF BUSINESS. ANY ADVICE? "
MAVELA MASEKO on Monday 11 February 2013
"Why don't you try the Garden Planner from Grow veg.com it is available for free for 30 days and now has a gallery feature which shows plans of other peoples gardens, farms and allotments? It has some great plans and it might give you some thoughts for your business venture."
s.hughes on Monday 11 February 2013
"Has anyone used CedarShield cedar oil penetrant (cedar oil, quartz rock and white mineral oil)to treat pine or fir 2" framing lumber for the raised beds? They claim its non-toxic and a one-time treatment for rot."
Chris on Tuesday 12 February 2013
"Wow - have not hear of CedarShield. Will have to check it out. But, given the ingredients you listed, I would think it would be totally safe and probably quite effective as long as it penetrated the wood deep enough. The Eco Wood treatment I used seems to be working well but of course time will tell. It's a proprietary and thus unknown recipe but supposedly made of plant and mineral extracts. There is an interesting discussion thread on CedarShield here: http://cr4.globalspec.com/thread/47195/Opinions-Wanted-Cedarshield-Petri-Wood-Permatek Of course there is plenty more out there on the web. "
John Paul on Wednesday 13 February 2013
"I didn't read all the comments so maybe someone already said this, but I have had great luck not treating the wood and separating the wood from the soil using weed blocking material. 7 years and counting without replacing a single board yet and in the NW that's pretty darn good. I must ad, that I also cover the entire bed in plastic - like a mini green house - during the raining seasons and winter. So the heavy rains are kept off the wood and under the wood I put gravel so it drains well all around the sides under the wood. They went grey over the summer which is not real pretty. "
Bob on Tuesday 26 February 2013
"Those sound like good techniques for protecting the wood. What kind of wood is it?"
John Paul on Tuesday 26 February 2013
"As a beekeeper we have been faced with rotting wood a lot.Some have started dipping wooden wear in hot beeswax with paraffin.They claim it lasts for years.On wood that does not come in contact with honey I use Copper Naphthenate.I used to paint but it just doesn't last. Too much handling chips it off. "
Keith on Tuesday 5 March 2013
"I constructed a redwood veggie bed and it does not look good next to the house. So we want to cover with stucco. Has anyone done this? Did you treat the wood? Use a metal lath? what kind? and what did you use as a weather barrier? My concern is that any toxics in the plastics and stucco could with time leach through the wood but I doubt it. What do you think?"
brenda on Wednesday 20 March 2013
"Stucco does not seem lke a good choice to contain wet soil. Stucco stains, and needs a fairly stable and solid base to have any chance at resisting cracking. The stucco on houses has a minimum code height of 6 inches above grade and there is a good reason for that. I would recommend a nice stain for your redwood veggie bed. As much as I hate to be the voice of reason, stucco would look horrible as a veggie bed."
Tim on Wednesday 20 March 2013
"not sure why it would be horrible. You see many planters around houses in stucco. Why can't they contain veggies. The problem is the safety of materials for an organic veggie bed. "
brenda on Wednesday 20 March 2013
"I happened to come across a u-tube video which is promoting using non-toxic RV waterline antifreeze...ie propylene glycol. http://www.youtube.com/watch?v=w2b564B3Rpg It sounds too good to be true, but I have used it in boat drinking water systems to protect from freeze damage, because it is "safe" to drink per the manufacturer. Does anyone know if it will actually protect wood from rotting in raised bed applications and not impact the soil or veggies? Thanks"
cliffc on Wednesday 3 April 2013
"Well Cliffc. I go 100% organic on my garden and take care to avoid toxins and chemicals. Propylene glycol is something I would never allow to leach into my soil to be absorbed by the plants I plan to feed to my family. Call me paranoid or a conspiracy theorist or just call me cautious. I don't trust the FDA further than I can spit. They are light years behind the times and do nothing to protect people. I'm sure the industry that produces and sells propylene glycol will claim it is safe until you either force them to drink a glass of it or someone forces them to tell the truth. With a little common sense, you can glean a lot of useful information from a material safety data sheet. (according to it, drinking it would be a very bad idea) http://www.sciencelab.com/msds.php?msdsId=9927239 Likewise, with a little common sense, you can glean a lot of useful information from sites like these. http://thegoodhuman.com/2009/03/31/what-is-propylene-glycol-and-why-you-should-avoid-it/ http://www.dogfoodadvisor.com/red-flag-ingredients/propylene-glycol-dog-food-aid-or-automotive-anti-freeze/ And finally, with a little common sense, ask yourself the basic questions, what is it, where does it come from, and that is all anyone needs to know about it. Propylene glycol is a petro chemical. I watched the video and it didn’t make sense, you are correct to question it."
Boom King on Wednesday 3 April 2013
"Boom King is absolutely right! I have always read and heard that PG IS toxic. Because its sweet dogs and cats sometimes lick up spills and then get deathly ill. "
John Paul on Wednesday 3 April 2013
"You might be thinking of Ethylene glycol John Paul. Both are used for anti-freeze, Propylene glycol is considered the safer of the two, but I would not give either to any animal or garden."
binary digits on Wednesday 3 April 2013
"My 2 cents... wood is cheap! Build your beds in a way that boards can be easily replaced. When the time comes, back out a couple screws and replace the board. Easy and worry free for however long a board lasts in your climate."
Practical Mike on Thursday 4 April 2013
"Thanks to Boom King, John Paul, binary digets and Practical Mike.... I decided to go with the local saw mill pine - full 2" thick by 12" by 12 feet - $20 each... Unfortunately I need about 15 boards which is a lot of organic veggies at the framers market, but I'm betting the boards will out live me, and I'll get a lot of produce over time... it's not about the money, it's about knowing and enjoying how your food is grown.. It's April and we still have butternut squash in the basement from last year here in RI. "
Cliff on Sunday 7 April 2013
"The question asked is for a science-based answer to the use of spent engine oil on timber used allotements and gardens."
Donald Thomas on Saturday 13 April 2013
"I thought of this idea yesterday to use styro-foam as a liner inside your wooden garden's and have controlled drainage by making strategic holes which will drain away from the wood. Question is how to get hold of styro-foam that will fit? They often discard large sheets of it from appliance boxes and maybe one can cut out the foam and glue them in place with natural bluegum tree glue or something. i think i should try this. "
Bradley on Wednesday 17 April 2013
"After reading this, I am truly surprised at how many people lack basic common sense. The idea of growing veggies in chemical or petro products just screams "NO!". Plastics and all petro chemicals leach toxins and poisons into any moist soil/water they are in, plants absorb everything they can from the soil they grow in including toxins and poisons. 1+1=? Polystyrene foam aka Styrofoam is nasty stuff when it comes to the environment and human health. Admitted, it is a great insulator and great for buoyancy and has some great uses, but contact with food and agricultural soil is not one of them. It is full of BPA, styrene is a human carcinogen, it breaks apart easily, so good luck tilling soil around it. Everything about it screams really bad idea, and that really is a no-brainer. I like what Cliff from RI said (above), Just go with some good untreated local lumber and enjoy your garden. The CedarShield stuff mentioned above sounds interesting and worth some investigation."
Elliemental on Wednesday 17 April 2013
"I've been searching for a truly safe preservative for my vegetable planter boxes and I'm not 100% convinced about the safety of Eco Wood Treatment or the suspiciously similar LifeTime Wood Preservative. I researched this for hours. According to the material safety data sheet (found on homedepot.com), the amount of a secret proprietary ingredient (accounting for less than 50% of the product) required to kill half the number of rats in a test group is 1480 mg. per cubic meter (.05 oz.). It makes some other odd statements, like referencing a soon-to-be-received confidentiality number... (I checked the Canadian EPA, toxic substance act, industrial research council...) I also don't trust supposedly official documents with misspelled words either, so the risk to my "GI TRACK" or aggravation of "dematitis" or the potential for "very irritation" are in question. Nothing on their or their partners websites claim the product is food-safe, which it would have to be in order for me to plant my carrots or tomatoes near it. (They also say to use triple strength solution where there is soil contact.) There just isn't enough information or documentation to make me believe its claims, though they are repeated everywhere, unchallenged. I can't accept this product as food safe based on the "sham-wow" internet presence. I've decided it's best to let the wood go naturally and leave it at that."
Ellenbee on Thursday 18 April 2013
"Useful thread, and refreshingly lacking criticism of each others knowledge levels (bar one!). I am involved with putting a raised bed in our town centre with 'Help Yourself' Herbs in it for the public. The challenge is to find a solution that is: Aesthetically pleasing, Long lasting, Safe for food, Sustainably sourced. My preference is wood, for looks, and untreated, for food, but the council understandably want long lasting and not a ridculous price tag. Stumped!"
Mimbles on Saturday 27 April 2013
"Have to congratulate Ellenbee on her determined research. My use of Eco Wood treatment was a gamble and, what I suspect is, that its not perfect but not terribly toxic either, based on all I have read about it. What is amazing to me is the thorniness of this endeavor; of trying to find the best solution and that there is no easy answer. Recently I became aware of a safe stain available in a green products store near here that might be an excellent alternative. Here is the description: "Safecoat DuroStain is a premium quality, fast curing flat finish semi-transparent stain for interior and exterior surfaces. It promotes penetration of porous surfaces and has high adhesion for superior protection as a decorative colorant. It contains no aniline dyestuffs, no gilsonite or asphalt, no aromatic solvents and no formaldehyde." The website address for those interested: http://www.naturalbuilthome.com/afm-durostain.html . This store is known for some of the safest, most advanced eco products around. I also am supportive of the idea of thicker and heavier plain old untreated pine or fir boards and I do think they will last quite a long time. Cedar or redwood is ideal except for expense and possibly the downside of using those precious woods. I think one of these three alternatives is best (1. plain, thick less expensive, completely untreated wood; 2. expensive, naturally rot resistant wood or 3. the least toxic possible coating on pine or fir) and totally agree with Eliemental about plastics and chemicals. What I did was what I thought was the best option at the time and still feel pretty good about it but one can always improve upon anything. "
John Paul on Monday 29 April 2013
"@ Mimbles I picture a low (2 foot) rock and mortar planter bed with a cap wide enough to serve as seating. Local rock, donated labor (perfect volunteer opportunity for someone to try to build some masonry skills), and you might be able to keep the cost down (you will most like want an automated drip irrigation system and possibly some lighting. It could be gorgeous and you might even be able to get some local businesses to sponsor it and even pay for a bronze plaque saying donated by business XXX (advertising). Design the herb garden to look good year round (main plantings of sage, rosemary, lavender, etc and strategic places for annuals like cilantro, basil, chives, nasturtiums, etc. (depending on your climate) I can't get too detailed on suggestions because you didn't mention size and location... A big planter in a southern location might benefit from a shade tree to filter sun on part of the planter. A bed in a northern location may be cold and harsh but may benefit from a juniper to provide berries. Perhaps you have room and climate for a cinnamon tree or a bay tree, etc. Wood is great for home garden planters because most are trying to maximize space for veggies. But for a public planter, rock and mortar can't be beat for durability and aesthetics."
Eliemental on Monday 29 April 2013
"Does anybody know the implications of painting an elevated garden bed with normal water based paint. Would that also leach out into the wood in time and cause any problems?"
Lee on Monday 13 May 2013
"I would think it would be fairly safe but there are some heavy metals and other potentially toxic ingredients in regular paint so you could go with low or nontoxic paint. Here is a list: http://eartheasy.com/live_nontoxic_paints.htm The thing about paint that I discovered in my research is that it doesn't provide the same protection as a wood preservative and, in contact with soil and water, tends to "bubble up" or wear off but, I imagine, it would extend the life of the wood significantly further than doing nothing to protect it. Of course, you theoretically would not need it if using cedar or redwood. "
John Paul on Monday 13 May 2013
"Why not use a dimpled membrane product to line the planter box? Like that foundation wrap they use. I would assume its an inert plastic that would be fine to use. It would allow the wood to breathe and dry, and allow water to drain."
Don't Worry on Monday 13 May 2013
"http://waterproofmag.com/back_issues/200801/dimple_membranes.php HDPE does not leach BPA, dimpled membrane should be safe to use as a veg planter liner. I will be using this to line cedar planters at our house this summer."
Don't Worry on Monday 13 May 2013
"Thanks for thee comments. I will bear both in mind and look into each."
Lee on Thursday 16 May 2013
"So after all this no one has an answer. Oh well. That's the way it goes."
lois malone on Thursday 23 May 2013
"I'm sorry Lois, the answer is no, followed closely by yes, and for good measure, let’s add in a definite maybe. What was the question? Oh well. That's the way it goes."
Tim on Thursday 23 May 2013
"We just created our 1st raised bed for veggies this weekend. We have tried several years of growing tomatoes and a few other veggies over the years with dismal results. We have clay soil. We've tried miracle grow (didn't help), mixing some sand in with the soil (didn't work), etc. So it was either buy a bunch of pots, or just build our own. We made it 6' x 2' and about 4' high. It actually serves 2 purposes. 1) hopefully the tomatoes will do better and 2) we made it higher than we wanted in order to block off the back of the shed to keep our digging dog from getting back there. She's jumped over our other attempts at keeping her out. She can't jump over this thing. After doing research, we bought treated lumber as it's no longer made with arsenic and anything else that may leach is really minimal. I wanted something that was going to last for quite a few years. Plus it's wonderful to not have to dig in the dirt on the ground. My husband has arthritis in his back. There is a trick to growing tomatoes that I just found out about...tear off the lower tiny branches/leaves and plant it deeper in the ground. http://bonnieplants.com/library/plant-tomatoes-deep-deep-deep/"
rrhoop5469 on Sunday 2 June 2013
"Wow - 4 feet! That is impressive. That is great and something raised bed afficianados often think is the ultimate, especially as we age. There are some wonderful soil amendment products these days that could have helped with your initial problem of clay soil. Compost is the best but there are also items by Dr. Earth, EB Stone, Fox Farm and Down to Earth. A cover crop like buckwheat or clover helps as well as amendments like vermiculite or pumice but the best is organic matter contained in compost and those product names I mentioned. Well composted or broken down manure is excellent too. Wondering about what you discovered regarding treated lumber. I have known for some time they no longer use arsenic but heard and read the chemicals they continue to use, though not as toxic, are still of great concern and not something one would want in an organic garden. Would appreciate any insights you have. Thanks. PS. Digging dog - terrier? "
John Paul on Sunday 2 June 2013
"Here are the first two links from Google regarding pressure treated wood. They are relevant. http://www.strongtie.com/productuse/ptwoodfaqs.html# http://www.finegardening.com/design/articles/pressure-treated-wood-in-beds.aspx CCA treated wood is still made, but it is no longer approved for residential use (Chromated Copper Arsenate, the stuff that leached arsenic). And while CCA has been replaced with other chemical concoctions that do not include arsenic, they are none the less, chemical concoctions and they do leach. We also know that wood does not lock those chemical concoctions away and that all will slowly leach back out and into the soil. Additionally, the newer formulations of treated wood still have other issues of concern. Some are far more corrosive to various metals, especially in a moist environment (such as a garden). So, depending on your choice of chemical cocktail leaching wood, you may need to go with stainless steel fasteners, or hot dip galvanized (toxic), but you cannot combine the two. You also might have to deal with build ups of white powdery film (corrosion) on the fasteners known as white rust. The problem is amplified exponentially if the environment is kept moist. The only wood treatment that I know of that is safe for any garden and will not leach is the Timbersil stuff (silicone wood) mentioned above. That stuff can be quite expensive and hard to get, so going with an untreated wood seems to be a better choice for most people. "
Troweler on Monday 3 June 2013
"Helpful info and I am in agreement."
John Paul on Monday 3 June 2013
""The idea of growing veggies in chemical or petro products just screams "NO!". Plastics and all petro chemicals leach toxins and poisons into any moist soil/water they are in, plants absorb everything they can from the soil they grow in including toxins and poisons. " - Eliemental I agree with some of this, but if you had a hard plastic (someone brought up HDPE) that doesn't leach any harmful chemicals, what's wrong with that? Untreated wood is fine until it rots from direct soil contact. Screaming "No!" right off the bat seems shortsighted. I would think there are some foodsafe "plastic" materials to use if one looks for them. "
Jon on Monday 3 June 2013
"Eliemental, please read this article about concerns with plastics: http://www.vitalearthminerals.com/are-all-plastics-bad/"
Jon on Monday 3 June 2013
"Hi Jon, Not sure what makes you think I am “screaming "No!" right off the bat”? I read your link and sadly, I did not find anything I have not already heard/read previously… I have a favorite saying that I thought up a couple decades ago, “Ignorance is the mother of stupidity”. I’m not calling you stupid Jon, but I will say that you are sitting in a hopeful state of ignorance. And I can understand that, considering the appeal of plastic is convenience. Have you ever come across a piece of HDPE that has been outdoors and exposed to the elements for a couple years? It’s brittle, clouded, deformed, cracked, etc. I’m not talking about the degradation on other plastics like cars with plastic bumpers, lawn furniture, and other non HDPE plastics. The reason for this degradation of the plastic is the leaching of chemicals by the sun and elements. It happens to all plastics and HDPE is no exception. HDPE aka High Density Polyethylene is a plastic. All plastics are “chemical concoctions” (to borrow a phrase). HDPE is a petroleum chemical byproduct, granted it is a little better than most, it is still a plastic. Common sense “screams no” to any chemical byproduct concoction derived from petroleum or any other “chemical concoction” for that matter. Your link to vital earth minerals only lets me know that they have gone out of their way to regurgitate the same misinformation that goes against common sense and claims that High Density Poly Ethylene is safe. It is also worth noting that they are claiming HDPE is safe for their “do not store in direct sunlight” bottles that will contain their supplements and vitamins for a short time. I found it hysterical that they spent the effort to talk about how safe HDPE plastic was only to directly follow it with a statement that we are all exposed to environmental toxins including toxic plastics and that is just a fact of life and that only the healthy survive so you should buy their supplements and vitamins so you can survive the very toxins they are selling you… LOL… Ironic… HDPE does not contain BPA, that is a good thing, but still just a drop in the bucket of chemicals it does contain. HDPE contains a lot of really bad stuff and the FDA only considers it safe for a container that will be used temporarily and is not subjected to constant moisture, sun degradation, and extreme weather. The FDA actually cautions against reusing HDPE plastics and warns against refilling HDPE water bottles. In 2009 A DC startup company built a plant to turn plastics into oil (including HDPE plastic soda bottles) . Here is the link - http://www.washingtonpost.com/wp-dyn/content/article/2009/09/15/AR2009091503264.html In 2010 a Japanese researcher Akinori Ito released a prototype of a machine (home appliance) that creates oil from Polyethylene using a small, self-contained vapor distillation process. It heats up the plastic and turns it into vapor and then turns it back into crude oil. The household appliance (that is how he designed it) only needs one kilowatt of power to convert about two pounds of plastic (Polyethylene ) into a liter of oil. We might see those in our homes in the future. Here is a link for that - http://www.smartplanet.com/blog/thinking-tech/new-invention-turns-plastic-bags-into-oil/6295 Now, tell me honestly… Doesn’t that just rub your common sense the wrong way Jon? Akinori Ito said he figured that if you could make plastic from petroleum chemicals, then you should be able to reverse it, needless to say, he was right. And all it took was some heat. My common sense is screaming at me that there is no way I want toxins, of any kind, anywhere near my organic veggies. But plastics was not a “right off the bat” decision. I have seen what happens to plastic when it has been outdoors, exposed to the elements, baking under the sun, freezing under the snow, pelted by the rain, etc. I have come across plastic in landscaping, and trash, lawn furniture, and all around and I know that the elements do a number on plastics, but they still take a very long time to break down. HDPE is more resilient than most plastics, but I have still seen some crumbly, clouded, cracked, and deformed HDPE water bottles that I know leached and dried out. That scream actually took a couple years to form but was irrefutable evidence that I could not ignore, not even by reading the plastic propaganda off the website of a company trying to justify hocking their wares in cheap plastic bottles. "
Elliemental on Monday 3 June 2013
"So what chemicals specifically does HDPE leach as it deteriorates? Over what period of time does this happen? Doing a Google search on HDPE seems to corroborate the argument I made of it being safe to use. I only pointed to one article, but there are several indicating the same conclusion. The washington post article you posted is broken. The other link indicates that it uses "plastics" but does not specify which ones. This is getting off topic as I'm not talking about subjecting HDPE to excessive heat. My garden temperature will not exceed the melting point of HDPE, nor get anywhere close to it. Please realize that I agree that other forms of plastic can be toxic from the chemicals they leach. I am specifically speaking about HDPE as it is a much more stable form of plastic, and I have yet to see SPECIFIC data for the chemicals you claim that it leaches."
Jon on Monday 3 June 2013
""HDPE is more resilient than most plastics, but I have still seen some crumbly, clouded, cracked, and deformed HDPE water bottles that I know leached and dried out. " --This statement explains how some HDPE plastics have weathered, but does not contain any specific information. Please display more fact than opinion. Objectivity wins the science race."
Jon on Monday 3 June 2013
"Common sense wins the science race Jon. Sure, you need objectivity, fact, control, data, and more, but those are tools and tools without common sense are as worthless as your weak and coy arguments. You read like a shill for the plastics/petroleum industry and are as transparent as a 3 mil sheet of Polyethylene. HDPE is made by applying intense heat to petroleum - a process known as 'cracking' - to produce ethylene gas. Under controlled conditions, these gas molecules link together to form long chains or polymers and produce polyethylene - a substance that looks a bit like porridge. This substance is then forced through holes into long strings, which in turn are cut to form granules. But this is a crude overview because thermal, UV, and other stabilizers/chemicals are added. It’s bad enough that we are talking about drinking out of solidified petroleum vapor, but that vapor has been mixed with all sorts of chemicals and all of that can and does break down under the relatively low heat and UV rays of the sun. “So what chemicals specifically does HDPE leach as it deteriorates?” It all depends on the recipe that the maker used Jon. Exxon has 28 different flavors of HDPE, Dow has 6 flavors, then you have Chevron, Shell, BP, etc. etc… And there are hundreds of low level petro companies out there Jon. My question is which one do you work for? “Doing a Google search on HDPE seems to corroborate the argument I made of it being safe to use.” I could care less what you Google Jon. I gave you the irrefutable common sense view that you can see with your own eyes. Which are you going to believe Jon? Big Oil/Chemical has a lot of money they pour into putting false info out on the web Jon… They may even pay people to go on blogs and spread misinformation. They also pay politicians a lot of money to let them do as they please. Do you have the ability to use that grey spongy thing between your ears Jon or are you just earning a paycheck? A school kid has the ability to do the basic science to prove you wrong Jon, heck I would wager that even you are smart enough to do the science… Go fill up some sterile HDPE bottles and some sterile glass bottles with distilled water and let them sit out in the sun all summer and tell me what they taste like in the fall. Do you think that foul plastic taste can “corroborate the argument you made”? You have shown your colors and I’m through with you Jon. I suspect we all are. Now go away and so the adults can discuss gardening. "
Elliemental on Tuesday 4 June 2013
"LOL! Amen Ellie! Jon, suck eggs dude! "Please display more fact than opinion"? Only a petrochemical shill would ask for something that a-retentive and totally asinine. I agree with Ellie 100%. I also agree that this is a blog about gardening. Jon, If you really want to know the toxic petroleum chemicals that leach from a plastic, then learn how to use a search engine. All I know is that if I accidentally leave a store bought water bottle in a hot car for a few hours, it taste nasty. That is all the proof I need and more."
Boom King on Tuesday 4 June 2013
""Jon, suck eggs dude!" - Ah, I see the adults have shown up Elliemental had mentioned. Don't worry I'll be on my way. This is now deteriorating to personal attacks rather than answering questions. I seem to now be a "petrochemical shill" for questioning the assertion made that HDPE will leach chemicals in a garden environment. Even though no chemicals have actually been listed. "
Jon on Tuesday 4 June 2013
"I have regularly used HDPE bamboo barrier to control running bamboo, and if it is underground, where the roots of plants are, it does not change appearance at all in at least 25 years, based on my experience. The environments that would cause it to break down would not support plant growth. I believe that it could be broken down if left out in a harsh enough environment for long enough, but what we are talking about is Death Valley for 500 years. The complaint with plastis in landfills has always been that they last almost forever if we bury them. Whey do they last forever in a landfill and break down if we bury therm in our yards? When we want it both ways, people no longer take us seriously."
Greggo on Tuesday 4 June 2013
"Cheap, do-it-yourself versions of the so-called "Eco Wood Treatment" or "Lifetime Wood Treatment" are available. Check out https://www.youtube.com/watch?v=eyF_ulsznlU for an example."
Jim on Tuesday 4 June 2013
"Here's another video supporting the use of baking soda: https://www.youtube.com/watch?v=qugVIOYi1xc. Got me wondering if the secret ingredient in "Eco" or "Lifetime" is something as simple as baking soda or some other simple alkaline material."
Tom on Tuesday 4 June 2013
"The green powder in Lifetime or Eco Wood Treatment is ferrous sulphate and the white powder is actually baking soda. The leaves in Lifetime are tea leaves to provide a bit of tannin; Eco grinds them finder so they don't clog spray jets. See http://buildingtree.ca/products-page/concrete-finishes/ferrous-sulphate-powder/ Note that Lifetime/Eco/Driftwood all sell for about $10-20 per ounce whereas Ferrous Sulphate costs less than 50 cents for the same quantity."
Jack on Tuesday 4 June 2013
"Jim, Tom, and Jack seem to be hijacking. I found some stuff online that effects HDPE, but its mostly strong stuff like xylene or REALLY strong acids or bases, not stuff you'd find ina garden. I dunno, I'm sure if you beat it or leave it exposed to the sun for years or use harsh chemicals on it, the results wouldn't be good. But in the ground, without all that happening I don't see if its all that bad. "
Don't Worry on Tuesday 4 June 2013
"Hey, this thread started off talking about how to treat wood and now it's switched to HDPE. Sorry if bringing the discussion back to wood treatment is considered hijacking, but I'm not the only one."
Tom on Tuesday 4 June 2013
"I agree with Tom completely. The discussion on hdpe is dead and over. Ellie and boom king nailed that coffin shut, hdpe is a big fat no. Besides, noone was talking about burying it underground to begin with, we are talking about raised bed gardening, full sun, and hdpe is not a wood treatment. Go start your own thread if you feel the need to discuss gardening in petroleum products. Back to the real topic of this thread, before it was hijacked by the petro-chemical shills, treating wood for veggie gardens... I am intrigued by this Ferrous Sulphate stuff. Does anyone know if it is toxic or if it breaks down into something bad my veggies might suck up in their roots? Or is it completely harmless like baking soda, aside from changing soil ph. And do hardware chains carry it or do we order it online? Has anyone tried it on wood?"
binary digits on Tuesday 4 June 2013
"I don't know much about it but it is used as a lawn fertilizer to prevent yellowing of grass, and it's also referenced here: http://www.motherearthnews.com/organic-gardening/seasonal-gardening-zmaz86mjzgoe.aspx#axzz2VGYycLwi and is supposed to help control moss growth. It's also commonly used in heritage wood tinting formulas where it's known as Green Copperas. Who knows, maybe you'll end up with greener spinach in a raised bed frame treated with the stuff! In any case, as far as I can tell it doesn't do anything to preserve the wood, just turns it grey. "
Tom on Tuesday 4 June 2013
"Binary Digits, This is probably what you're looking for: http://www.tpsgc-pwgsc.gc.ca/ongc-cgsb/programme-program/normes-standards/internet/bio-org/permises-permitted-eng.html Ferrous Oxide is listed as a "Permitted Substance" in Organic Farming."
Tom on Tuesday 4 June 2013
"... and it's supposedly used in baby food as an iron supplement!"
Tom on Tuesday 4 June 2013
"Sweet! If it makes wood look good and controls moss growth, then it will most likely prolong the life of the wood. And it is good for you to boot. I'm diggin this Ferrous Oxide stuff. Looks like I could apply it to a newly built planter bed, inside and out with a garden sprayer."
binary digits on Tuesday 4 June 2013
"As for where to get it, see the link Jack made above or http://www.artantiquequebec.com/en/ferrous-sulphate.htm ... looks like it simply accelerates and gives an even grey weathering look, but whether it protects the wood, I'm doubtful"
Tom on Tuesday 4 June 2013
"Ferrous sulphate (not ferrous oxide) is widely available as granules in garden supply outlets for use as a soil additive to increase soil acidity (lower pH). That said, I have no idea how benign it is or whether it meets stringent organic guidelines."
bill on Wednesday 5 June 2013
"So, after four years, how's the wood holding up? We are just embarking on this gardening voyage. Thanks for the article!"
Sonia on Tuesday 30 July 2013
"beeswax. better if hot/ melted, and then you dip the wood. Or paint it on, depending on whether you treat the wood pre or post constructing the beds. Otherwise an old old fashioned wood preservative in South Africa is Aloe ferox juice. Works."
suzanne on Tuesday 30 July 2013
"I'm built 2 beds using Hemlock in 2012 (like cedar but considerably less $$$). The wood is sold "green" meaning it hasn't been kiln dried like most other wood available for sale. After the first year, they've turned grey, but are as strong and durable as they were when I first made them. I'm expecting 10+ years out of them."
Clayton on Monday 23 September 2013
"So it's been 4 years, what's the verdict? Thx for the article"
Nuno on Tuesday 24 September 2013
"So....I just found this weblog....four years running... What's the verdict? I don't care about looks really, but I do want a raised bed and, only need it to last 3 to 5 years. . It will be a very large perimiter so I assume hardwood is too expensive and pine probably won't make it 3 years (or will it?). What is the state of the state in recycled plastic boards specifically for beds? When it comes to them all I care is that they leach NOTHING. IF it has been proved that after 3 or 4 years they still leach nothing and ssuming cost is less than hardwood..I will go with them"
Like_Them_Termaters on Sunday 6 October 2013
"Hi I just purchase some 528 58 H4 EcoWoods OUTDOOR TIMBER at the local gardens supplies he said that it is fine. I can not seem to find any information about is it ok for veggie garden box. I also have thing about lining it with a think garden plastic just in case what do you think. Thanks Stephen"
Stephen on Friday 1 November 2013
"So, it’s been 5 years. How’s it holding up?"
Mitch on Thursday 6 February 2014
"In October 2011 I added to this thread as follows:- 'I put black polythene DPM 500 gauge, as used under concrete floors, to line the sides and bottom of the bed. I put numerous drainage holes in the bottom layer so that any excess water will escape. Am I now in trouble with chemicals from the polythene being a potential problem? I would be grateful for any help and comments from all of the experts out there.' Since then a few people have touched on this but no one has really given me a definitive answer. We are still growing veg in this bed - about to start our 5th year - and as far as I know we are still healthy but we could be slowly killing ourselves! Does anyone know for sure please about potential toxins from black DPM polythene?"
Michael Clare on Friday 7 February 2014
"What if someone told you it was ok to use boiled linseed oil on the boards surrounding your garden. Is there any fixing this? Can I go over it with raw or something to "seal" in the bad stuff that could leach into the soil from the Boiled linseed. Or do I need to scrap the boards altogether and rebuild the whole garden? I'm not necessarily trying to be organic, just not add to the chemicals we are already probably getting from other things. :) Any suggestions would be greatly appreciated!"
Jennifer on Sunday 4 May 2014
"Consider that there are somewhere in the neighbourhood of 100,000 chemical substances introduced into our environment. Each of these chemicals can potentially interact with living organisms (including humans) in thousands of ways. Adverse effects may be decades in developing while the chemicals may linger in our environment for millennia. This long enduring complexity with all of the chemical “background noise” makes it impossible to link a single death to a single product. In the US we have a “use first, test later” system where political, economic and technical limitations means that none of the chemicals have been exhaustively tested, only a handful have been well tested and many haven’t been tested at all. Even if pure polyethelyne itself should be proven non-toxic, you still have to consider that your sheets may be adulterated with any number of other chemicals which the producer may or may not publicly disclose. Based on the fact that we are regularly in contact with thousands of chemicals whose safety is unknown or unproven and whose adverse effects can be both cumulative and interactive, it would be both prudent for ourselves and considerate to others not to add to the problem. "
bill on Sunday 4 May 2014
"Hi Jeremy, Just came across this post whilst researching materials and possible treatment for some raised beds I'm going to knock up. At the end of the article you said: "Ask me in five years time and I’ll tell you if I made the right decision!" I've just noticed you wrote the article 5 years ago! So.. what's the verdict?! "
Adam on Wednesday 5 November 2014
"Adam, thanks for the question! The beds lasted well for 3 years and then I had to move house and the new owner ripped them up! However, it was clear to me that they would easily survive another two seasons. That being said, in my new garden I built raised beds with locally sourced seasoned larch which (along with cedar in the US) is likely to last much longer untreated, since it contains natural substances which resist rotting. It was at least 50% more expensive though... I hope that helps. It would be interesting to hear other people's experiences around this too. I think in some very humid climates this wouldn't hold true, although, living near the coast, we get a fair bit of humidity here, although temperatures don't get very high."
Jeremy Dore on Thursday 13 November 2014
"Has anyone tried applying wood ash to untreated boards? Apparently there are wooden churches in Norway that are 700 years old, and they were preserved in this way. I imagine wood ash could be mixed with water and 'painted' on."
Duncan on Wednesday 25 February 2015
"Not sure if this has been asked as i haven't read every comment. Could you paint the inside of a vegetable planter with pond paint? Waterproof and non toxic, it should be good solution instead of using plastic liners. "
Max on Sunday 12 April 2015
"Just a thought: bathe the wood in a mixture of beeswax and hemp seed oil. Probably what the tar and pitch consisted of in the Old Testament building of the ark. "
George A. on Friday 1 May 2015
"Someone earlier posted the following - Eco Wood Treatment, which seems good. It grays the wood, which, for me, is a deterrent. http://www.ecowoodtreatment.com/video.html In researching the above, I found the following - Agra Life Lumber Seal - which also claims to be completely non-toxic, good for food producing plants. It is also a clear coating, so natural color will stay present - though not sure if natural greying will occur over time. I am still investigating ,but thought these two links may be helpful for others. http://www.homedepot.com/p/TriCoPolymer-VOC-Free-Non-Toxic-Lumber-Seal-1-gal-Clear-Satin-Wood-Sealer-LS128/203322573#product_description"
Stuart on Wednesday 20 May 2015
"Someone earlier asked about using fiberglass for the lining of the cedar planter. I'm curious if anyone has any info on if this is just as bad as using plastic? "
Src on Saturday 6 June 2015
"I have hard wood timber and am wondering if i sump oiled the boards would it effect the vegies?"
scott scantlebury on Monday 12 October 2015
"Excellent post with a lot of good information. My wife and I opted for cedar planks treated with thick coats of raw linseed oil. It was very costly, but we believe it will pay off in the long-run. "
Gordon on Sunday 17 April 2016
"We used Eco Wood Treatment on pine in 2011 for our greenhouse. It did grey the wood, but it has not rotted and has held up very well. We live in Canada, south eastern Ontario, so the weather ranges from very very cold in winter, wet and rainy in the spring and very hot in summer. I am happy with how it has stood the test of time. "
Dania Madera-Lerman on Sunday 17 April 2016
"Hay bale gardening. Raised beds using 2x10x10 cut to fit the measurements of multiple hay bales laid end to end, Look for a local source of bales and how to online . Gardeners catalogue has aluminum corner braces. "
jay on Tuesday 26 April 2016
"Thank you so much for this article! I've recently purchased a very large raised cedar planter, with the plan being to start an organic vegetable garden for my family. I want to preserve the planter of course but it defeats the purpose of having an organic garden if toxins from the preservative will be absorbed into our food anyway. I am just going to leave it as is. Thanks for the article."
Jess on Friday 6 May 2016
"Great topic and well written. Do you have any more resources about this that you reccommend?"
Lafountain on Sunday 29 May 2016
"It's been five years. How did your untreated wood beds hold up?"
Elle on Monday 6 June 2016
"Plain pine, Untreated, two years and still there and holding I made it such that as the boards rot they are easily replaceable. a little dirt will spill out when I finally have to replace boards but no big deal. No toxins, no messy linseed. Just a little extra work every 3 (or maybe even more !!) years "
CJ on Monday 6 June 2016
"I use a cashew based wood finish with zinc borate. The cashew is safe and strong against water and the zinc borate doesn't leach out, but even if it did the plants would put it to good use. This is the best long term solution I've found. "
GL on Tuesday 26 July 2016
"For my first bed, I used plain, untreated pine boards. 2 inch thick from Home Depot. They lasted five years so far but probably only 1 more year left. The screws are beginning to pull away so they are about finished. For the additional beds that I built the following year, I used raw linseed oil. At least 3 coats until the wood stopped absorbing the linseed oil. They have not lasted any longer than the original bed with no preservatives used. I live in hot, steamy Atlanta, GA and grow all four seasons."
Joanie on Friday 5 August 2016
"Just use large rocks to create a raised garden. Easy to use, durable, and totally natural."
J on Monday 14 November 2016
"I'm 82 and began gardening with my mother's hovering oversight when I was five. I'm still learning and still gardening. I read all the comments above. I learned about cold beds from my older brother who got it in Ag.class in 1942. I was 8 and kept it in mind 'till about 20 years ago. Our 4'x 8' untreated #2 Pine frames lasted seven years. Standardizing size and design has some advantages. This time, I'm going to use a 12"pine board for the north (back) side and a 4" front. The 4-foot sides will slope from 12" to 4". The frame will sit in a 2" ditch all the way around to seal against cold air. THIS IS A COLD BED APPLICATION.Cold beds are used as far north as Ohio and east of there. Grows slow and requires less water than summer. Additional frames can be added on top of the base frame, 4" or 6" or 8" to accommodate taller crops. The crown frame will be 2x4 covered with chicken wire to support 6-ml industrial grade plastic. Plastic will cover the top and underside with no hinges. Crown frame can be raised with a loose 2x4 block at each corner. Industrial grade plastic is strong, milky. It lets plenty of sun through. Deciding to use plain lumber and let the termites have their share is the easiest and safest way (for me). If you get 5-6 years out of a frame, you have won! Make one new frame each year improve the design if need be. My eye surgeon told me to eat plenty of greens, that's the best protection we have against macular degeneration. So, using cold beds and planting greens in October (Alabama)gives a bug-free harvest.Steam the greens 10 minutes, transfer to pressure cooker for 10 minutes and it's over. Freeze it in small containers. The cold bed crop will continue growing slowly all winter and into spring. (You have to be home to air the beds when they get hot.) Cold beds also give you an early start at spring gardening if you sprout the seeds in the house and transfer to the cold bed. In the house (winter) I eat a lot of sprouts raised in quart jars, added to salads or ground up in a little Oster blender jar and used at breakfast. Digests easily and winds your clock with energy. The Great Depression was a great teacher for us all. (No, we didn't eat sprouts during the depression and didn't have electricity.) But, my mother's ability at gardening and canning kept us fed well during those tough years."
Dan Carr on Tuesday 27 December 2016
"Thank you Dan Carr. Well said. I like your strategy. Be well and Happy New Year "
Chris on Sunday 1 January 2017
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Pete on Sunday 1 January 2017
"I wonder if anyone has looked into using wooden wine boxes for planters and knows whether those boxes are treated with anything? Alys Fowler, who grows organically, advocates using them, though she also recommends treating them with products that seem to be potentially toxic from the information in this article. Are they treated? Many thanks."
Elizabeth on Wednesday 8 February 2017
"Traditional and absolutely organic way of treating wood to go in soil is...? Nobody uses it here? Well I will get thicker material for the beds and the side exposed to soil threat this traditional way. Just simply partially burn the wood. Make a nice fire. Wait for a nice layer of embers and place the wood on it for short controlled while. You can surely Google out the science behind it...."
Jacob on Tuesday 25 July 2017
"You started with some info in sealing concrete block beds and everoything after the first few articles were for wood beds. I'm desperate ad the contractors are coming back Monday to waterproof and I don't know what they are using but I'll bet it's tar. Any suggestions?"
Lucy on Friday 11 August 2017

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