Using Milk to Prevent Powdery Mildew

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Squash leaves can be susceptible to powdery mildew

You don't have to garden long to become acquainted with the disease called powdery mildew, which creates whitish patches on the leaves of pumpkin, winter squash, and other members of the cucumber family. A fast-growing fungus, powdery mildew is also among the worst enemies of rosemary, and is a well-known disease of monarda, grape, and zinnia. Each of these unrelated plants hosts a different strain of powdery mildew, but I have found that they all can be controlled with regular sprays of milk and water.

What is Powdery Mildew?

To understand how milk sprays prevent powdery mildew and thus use them most effectively, you must first understand your enemy. Powdery mildew fungi are present in many environments, so that even in the cleanest gardens, outbreaks can begin from spores spread by windblown rain, or on the feet of insects and birds. But when the right strain of powdery mildew finds a suitable host plant, it quickly sinks root-like structures into the cells on the leaf's surface. There is stays, taking nutrition from the leaf while developing a matrix of thread-like structures over the surface. This is when we gardeners notice unusual patches of white or light gray with a powdery or furry texture, usually on the top sides of leaves.

Powdery mildew electron microscope image. Picture courtesy of the Max Planck Institute
Powdery mildew electron microscope image. Picture courtesy of the Max Planck Institute.

For the infected plants, powdery mildew cripples its ability to conduct photosynthesis by blocking out light, and stops up the leaf's gas exchange system, too. Powdery mildew can quickly spread to nearby leaves, so it's always a good idea to clip out leaves that show early spotting. Also make use of resistant varieties of cucumbers, squash and melon, which can be of tremendous help in preventing powdery mildew. Resistant varieties have special characteristics that make it extremely difficult for powdery mildew fungi to enter leaves, which they do with cell-melting enzymes.

Using Milk for Plant Mildews

More than 50 years ago, researchers in Canada discovered that milk sprays could help prevent powdery mildew on tomato and barley. Then the age of fungicides began, with no further published research on the milk cure until 1999. Since then, numerous small studies from around the world have validated the use of milk sprays on powdery mildew on a wide range of plants. Most recently, a spray made of 40% milk and 60% water was as effective as chemical fungicides in managing powdery mildew of pumpkins and cucumbers grown in mildew-prone Connecticut. In Australia, In Australia, milk sprays have proven to be as effective as sulfur and synthetic chemicals in preventing powdery mildew on grapes. In New Zealand, milk did a top-rate job of suppressing powdery mildew in apples.

Milk also prevents powdery mildew on grapes
Milk also prevents powdery mildew on grapes

Scientists are not exactly sure how milk sprays work, but most think proteins in the milk interact with sun to create a brief antiseptic effect. Any fungi present are "burned" into oblivion, but there is no residual effect after that. In order to be effective, milk sprays must be used preventively, must be applied in bright light, and should be repeated every 10 days or so.

On the downside, some writers have suggested that milk sprays give off a bad odor after they have been applied, but this has not been my experience. I use a hand-held pump-spray bottle to wet both sides of the leaf until it's dripping, and usually spray in mid to late afternoon on a sunny day. In the days that follow, I never smell a thing.

Healthy squash showing no sign of powdery mildew on their leaves
Healthy squash showing no sign of powdery mildew on their leaves

There is no consensus on which dilution of milk to water is best, with the most concentrated recommended mixture 40% milk and 60% water, and the most dilute 10% milk and 90% water. I fall in between using 30% milk to 70% water, with good results. It does not matter if the milk you use is skim or whole because it is the protein rather than the milkfat that is working on your behalf.

With experience, you will learn which types of powdery mildew are likely to develop in your garden, and this knowledge will take you far in managing this disease. Like other fungicides, milk sprays work best when used preventatively, before the disease can gain a foothold. If you often see powdery mildew on your squash, grapes or zinnias, start milk sprays before the plants show signs of infection. You have nothing to lose beyond a cup of milk.

By Barbara Pleasant

Electron microscope photograph of powdery mildew from the Max Planck Institute for Developmental Biology.

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Show Comments


"Excellent article! I am printing it off now! I live in Connecticut and powdery mildew has destroyed countless numbers of my beautiful plants! Thanks!"
Madonna Kilcollum on Friday 18 May 2012
"What great information! My squash, cucumbers and I all thank you profusely! "
George Angell on Friday 18 May 2012
"Has anyone else had difficulty with this page? On my computer, the text continues too far to the right, covers the 'categories' column, and is difficult to read."
green thumb on Friday 18 May 2012
"Great idea; I'll try it this year! I'm using Google Chrome as an internet browser and can read this website completely fine. "
Christian von Boehm-Bezing on Friday 18 May 2012
"Green thumb - which browser are you using? The page should be working correctly for you but we've had a couple of people report this in the past month and are trying to work out what might cause it."
Jeremy Dore on Friday 18 May 2012
"Thanks for this article! I will definitely be trying it. I was wondering, would powdered milk work as well?"
Alberta on Friday 18 May 2012
"Will this work for roses?"
Julie on Friday 18 May 2012
"Powdered milk has been used in some experiments, as well as whey, a byproduct of cheesemaking, but the little science we have here is based on supermarket fresh milk...Julie, milk sprays will likely suppress powdery mildew on roses, but may not give successful prevention of blackspot. Many newer roses have excellent black spot resistance."
Barbara Pleasant on Friday 18 May 2012
"Do you know if the milk spray will work on hops?"
Jody on Friday 18 May 2012
"Here is a quote from an article I just found. Copy and past link is below for the full, very interesting article. "Meanwhile, anyone can test the milky solution to mildew in his or her backyard garden. Crisp recommends using dry-milk powder?15 grams for every liter of water. So far, he finds, this formulation appears to work on all surface mildews." "
Sandi on Friday 18 May 2012
"Jody, milk will probably help with powdery mildew if used preventively on hops. They are not supposed to, but I think milk sprays are helping a bit with a bad year with hollyhock rust. My grapes that get milk sprays seem to have less brown rot. When trying any spray on a new plant, I test it first on a few leaves to make sure there are no negative effects. "
Barbara Pleasant on Friday 18 May 2012
"will this help with white spot on mustard greens"
gail on Tuesday 22 May 2012
"it is really great topic.. Iam a master student at Uni Adelaide. Iam doing my research project on using milk to control powdrey mildew in horticuticltiral crops and I've found that the high concentration of milk the more effective control. Also, the more frequencies of spraying milk the less disease severity. Iam wondering if anyone has relvant articals, could you please send it to my email address and I will be appreciative. Many thanks "
Sadya on Tuesday 22 May 2012
"Sadya, the boldfaced words above will link you to the latest research papers...Gail, I am always reluctant to spray anything on leafy greens because they seem to pick up off flavors so easily, and I don't know about the safety of eating leaves coated with milk residue. Mustard is so short-lived that it might be better to start over with a new sowing. "
Barbara Pleasant on Tuesday 22 May 2012
"Add a tablespoon of baking soda to the mix in addition to a few drops of ivory liquid soap.This adjusts the PH to an undesirable mildew atmosphere and friendly soap is an adherence agent"
TJ on Wednesday 23 May 2012
"Green Thumb = I have had the same problem with the text "scrolling" off to the right and being unreadable when it "goes through" the right column of "search catagories". I don't think your browser has anything to do with it. I had the problem on my last computer and just got a new one. I still have the same problem."
rick gilmore on Wednesday 23 May 2012
"Thanks Barbara, it has spread so fast, this morning I was just thinking that I must pull them all up and start again."
gail on Wednesday 23 May 2012
"Thanks once again for a great home remedy! I will definitely try this this summer. Also, the comment from TJ sounds useful, I will experiment on different plants to see which is best. Just a note to Rick Gilmore – you probably have the same browser on both computers. "
Marsha on Wednesday 23 May 2012
"Good stuff...Another couple of ideas to stop Powdery Mildew are to use chives chopped up and steeped in water then prayed onto the plants. For a Homeopathic remedy use Silicea or Sulphur. Both are good remedies to cure fungal diseases. However, they should not be used simultaneously. "
Ian on Wednesday 23 May 2012
"Good information. I'm glad to know there are a variety of dilutions that work. I, too, am eager to know if the dry milk will work, as I don't ordinarily have liquid milk around. Might try both on two different stands. I've replanted cukes, and I find the late crop is really susceptible because powdery mildew has by now overtaken the squashes."
Lemonfair on Wednesday 25 July 2012
"This is the first year without powdery mildrew on my cucumbers but what I did different this year is leave the two vents to the greenhouse open day and night once the frosts had gone. It kept air circulating I think and that is what has stopped the mildew. I tried milk the other year but perhaps left it too late as the mildew was already present. "
Posey on Thursday 26 July 2012
"If it's the protein that's effective I wonder if soy milk would work? "
Rainbow on Wednesday 15 August 2012
"Too bad for me -I read this after my squash crop died from mildew and borers.....I am storing this article for next season. Barbara, can you address the borer issue too? I have lost my pumpkins, zucchini, and cukes 2 years in a row. "
Claudia M on Wednesday 15 August 2012
"I won't know for sure for awhile, but I think the milk is making a difference with my late crop of cucumbers. "
lemonfair on Wednesday 15 August 2012
"keep it simple. i just use 50/50 whole milk and water. no soap or bsoda needed. works like a charm, used it on butternut squash and yellow zukes. now i just need to get out there and spray my yellow cukes. guess it's been the year of yellow gardening. did lemony heirloom toms last year they were amazing!"
dkw on Wednesday 15 August 2012
"Any chance this will work on jackfruit? In Chennai, India and all of the small jackfruit pods that started sprouting from the trunk this year became covered in grayish mold and shriveled up and fell off. "
MR on Thursday 16 August 2012
"MR, pod molds often are caused by botrytis species, which are different from powdery mildew in that they thrive in damp conditions. When other fruits drop their fruits with mold, horrid weather is usually the main culprit."
Barbara Pleasant on Thursday 16 August 2012
"I know wood ashes around peonies help with botrytis. Have no idea if it would with pod molds, or hoe the wood ashes help, whether by changing pH or some other mechanism."
lemonfair on Thursday 16 August 2012
"Dear Barbara, What do think about the mechanism or the mode of action of milk on the leaf surface that help to stop powdrey mildew?????????? thanks "
Sadya on Wednesday 22 August 2012
"When used preventatively, it works. Milk has been used as a hand wash to prevent transmission of other diseases, like tobacco mosaic virus of tomato, so it's not the first time dairy has crossed the line into horticulture. "
Barbara Pleasant on Wednesday 22 August 2012
"I would like to subscribe to this blog. Thanks."
Colleen Zacharias on Thursday 23 August 2012
"sorry I only have questions. I guess the only question then is cost. Ok if you have a milking animal around, but is milk cheaper than sulphur? They harvest the sulphur in Bali. The sulphur workers get 7c kg for the rocks. They have to climb a mountain to get it and carry it down in buckets on their shoulders. Industrially farmed cows do fair a little better, if the farmer cares. We just want to get the mould off the grapes but what's the cost? Permaculture with integrity!"
nexus on Sunday 26 August 2012
"hi does it mater if i use USDA organic milk OR market milk not organic? "
issa on Wednesday 29 August 2012
"Issa, that is a matter of personal choice. Use what you buy normally. At my house the choice is organic milk."
Barbara Pleasant on Wednesday 29 August 2012
"raw works best"
TJ on Wednesday 29 August 2012
"ok thank you guys for info. "
issa on Wednesday 29 August 2012
"i like your info but i will try to my tabal grapes farm "
nandkishor shinde on Sunday 16 December 2012
"shit i known that for ages its the best cure for powdery on grape vine and for downey milldue.............."
adam on Wednesday 13 March 2013
"All I have is soy milk so am giving it a try on my mold on tomato plants. Hope it works!"
Sharon on Monday 8 April 2013
"I was intrigued by this method and went outside to spray my tomatoes with a solution of it, only to realize I had reached for my lactose free milk, as that is all I can drink. I don’t mind buying a small pint of regular milk for this, but would anyone know if the lactose free milk works just as well? Thanks very much!"
Laura on Wednesday 10 April 2013
"Follow up, the soy milk worked!"
Sharon on Wednesday 10 April 2013
"Laura,i get the best results from normal milk,not that i have tried lactose free milk."
adam on Thursday 11 April 2013
"Yes, I think I will, just to be safe. I have 4 days of rain coming in, so when it’s over with and the sun comes out again, i’ll spray again with the regular milk. Was already well underway with the spraying when I realized I had reached for the lactose free out of sheer habit! "
Laura on Thursday 11 April 2013
"Am very surprised that soy milk worked, as it isn't in fact milk. I wonder if any of the rest of you have any experience with this? I'm hoping to try reconstituted dry milk rather than fresh milk, as I don't ordinarily drink milk. Any experience with this? Alternatively, I guess I could freeze portions of fresh milk."
lemonfair on Thursday 11 April 2013
"I had a terrible problem with powdery mildew last year with my squash and cucumbers. I have to garden in large pots where I stay at. I've done well without problems until last year. I want to take proactive action this year. My cucumbers are up and should be putting out vines by next week. My Squash should start blooming maybe in a week or two. I'll start spraying a milk mixture tomorrow. "
Sam on Sunday 14 April 2013
"ok it has just taken me 4 days to defrost my milk i left in the frezer. i dont think it is going to work as well as fresh i have been spraying milk on powdery for 8yeares,as i can see,try and just use fresh milk,it works for me adam."
adam on Friday 19 April 2013
"does it do anygood to spray the garden bed before planting if I had powdery mildew last year does the spores hang around in the garden over the winter. I live in Miamie Valley area of Ohio"
Ginger on Monday 29 April 2013
"Ginger, see if you can find resistant varieties for the plants that suffered from PMildew last year. The spores will be present in late summer no matter what you do because they travel on the wind. Depending on the problem plant species, resistant varieties may be available."
Barbara Pleasant on Monday 29 April 2013
"I can say my cucumbers and squash were doing great. I would have been harvesting squash by the end of next week. I've been using the milk spray about once a week and my plants were beautiful. The hail storm we had Saturday night pretty much ruined my garden. My tomatoes may make it but they are busted up pretty bad. "
Sam on Tuesday 30 April 2013
"My neighbor in the community garden planted Marketmore 76 and had nowhere nearly as much powdery mildew as I did only 35 feet away. I had planted a few hybrids. It was High Mowing Seeds Marketmore 76, but I'll assume the variations are slight and this variety might do well from any company. I've had good luck with the squashes listed as PM resistant from Johnny's seeds. And Sam - so sad about your hailstorm. Hope you can replant."
lemonfair on Tuesday 30 April 2013
"I replanted cucumbers and a few squash plants today. I had raised both the pre hailstorm cucumbers and squash from seed. I was forced to go to Lowe's and purchase plants this time before the summer heat hits here in southern Tx."
Sam on Tuesday 30 April 2013
"Hail can be such a heartbreaker. Last year one half-hour storm devastated everything I had growing. Good luck with your recovery. "
Barbara Pleasant on Tuesday 30 April 2013
"After reading this article I went home and tried the milk spray on my plants. And it really works. My shoe flower plant affected by this powdery mildew is growing healthy again and that too in just two days of usage. Thanks for the amazing information shared. "
aditi on Friday 24 May 2013
"Yes, milk works. But there is yet an other option, that uses no liquid and leaves no residue on the plants:"
Arne Aiking on Sunday 26 May 2013
"It was a very good article. Was as comprehensive. Thank you for your messages I send from Iran."
reza on Saturday 1 June 2013
"After you made the milk solution do you store in fridge? I know this sounds silly, but I'm afraid to spray cold substances on my plants...but afraid not to refrigerate in fear of milk souring.....thanks for answering what is probably a silly question...but I'm very beginner new to"
Mandy Murphy on Saturday 15 June 2013
"Mandy, it's best to mix up only as much as you need, because milk will go sour and the mixture will get too gunky to go through the sprayer. "
Barbara Pleasant on Monday 17 June 2013
"In Southeast Texas and already up in mid 90's here. I planted my 1st veggie garden this past Fall and now have planted 1st Spring veggie garden. Have lost MOST ALL of my Yellow Crookneck Summer, Zucchini, Acorn Squash and my Pumpkins, to the DARN Squash BORE!!:(:( GRRR!!!:( Will this also work AFTER the BORE has already "invaded" the vines, and the plant is MOSTLY dead? OR, can I cut the ends off which still are green and flowering (some have "roots" coming off vines), replant and give some root stimulator to help continue growing? Or (3) should I replant my seeds for new ones to grow? Thankfully, my Cantaloupes are doing fine so far - LOTS of flowers and vines running everywhere with SOME "little tiny" melons beginning to form! :) Thanks for any advise! :)"
Brenda on Friday 21 June 2013
"Vines that have developed supplemental roots often recover from borer attack and go on to produce more fruits. You should plant summer squash again, but not until late July or early August. Consider growing butternut winter squash, which is naturally resistant to squash vine borers. If you start seeds in a couple of weeks, they should make a nice crop. "
Barbara Pleasant on Friday 21 June 2013
"I have tried the milk spray and i used a 50/50 mixture. I am in Florida and i spayed on a hot sunny day and it did great. Almost and instant result. My plants loved it. The greenery was so health looking they almost looked fake. Not only does milk work as a fungicide but it also works as a pesticide. Many growers use milk because it is organic to spray plants they will be harvesting from soon. I talked to a local grocery store and told them what i started doing and they are going to give me milk that goes out of date that day. It is not only a better way to utilize all organic methods but it is making good use of milk that would be otherwise thrown out. "
Kevin on Saturday 29 June 2013
"Kevin: Glad to know the higher concentration worked. Do you know what pests it seems to discourage? Anybody know if milk discourages downy mildew. One of my community gardeners got some downy mildew on a cuke. Never seen it in our gardens before. I'm also thinking of combining milk and Surround. Anybody combined milk with anything else in the sprayer? Sea weed?"
lemonfair on Sunday 30 June 2013
"Compost Tea, baking soda and Honey"
TJ on Sunday 30 June 2013
"I have a mature peony plant that didn't have many flowers this year and now it is covered with mildew. I'm going to try the milk mixture spray and add some baking soda to it. Since this at this time is not preventative but hopefully curative I hope it works. Thank you all for your advice."
Wanita on Friday 5 July 2013
"re.downey and milk spray,i have sprayed milk on downey mildew last vintage on my grapes and got a good result,i picked the hottest day with open sky,i know somebody that combined milk and molasess together,didnt work to well aust.."
adam on Saturday 6 July 2013
"Brenda re: squash vine borer. I have lost my zucchini's every year from the borer until this year. I read that radishes will deter them if planted at the same time and left to grow. It is large and flowering and I have had no problem with borer. Don't know if it is the radish, but this is the first year I haven't had them attack my squash. I did apply diatomaceous earth at base also, but it rained immediately and wash most of it away and I have not reapplied."
Karen Smith on Thursday 11 July 2013
"Just noticing that there's a picture at the top of the blog with zucchini plants, showing the characteristically white color patches that some varieties of zucchini have. These are not powdery mildew patches. Some people in my community gardens get confused about that, and I've seen pictures online of zucchini as having powdery mildew when it's just a variety color pattern. If the zucchini up top also has powdery mildew I can't see it."
lemonfair on Thursday 11 July 2013
"Good point, lemonfair. The "silverleaf" characteristic is common in other squash, too. It looks very different from the dull fuzzy patches of powdery mildew. "
Barbara Pleasant on Monday 15 July 2013
"Has anyone tried combining milk and Surround in a sprayer? lemonfair, did you try?"
Patti on Tuesday 16 July 2013
"I have put both on at the same time, but didn't combine in a sprayer. Surround tends to clog up the sprayer, especially if applied at the recommended strength. I mixed up the Surround in a gallon milk bottle with most of the top (but not the handle) removed (a very handy jug for lots of things), added a couple of drops of dish soap because the surround is very reluctant to stick to the bottoms of leaves, and painted the surround on with a new paintbrush. Worked for what I needed to do. When the plants get bigger it will be worth using a sprayer. It has been very wet here, and so far I don't have any powdery mildew on any of my plants. Neighbors in the community gardens have yellow spots on squash, but no powder yet visible on the surfaces. "
lemonfair on Tuesday 16 July 2013
"lemonfair what is surround,i have'nt heard of it before,we might call it some thing different in austadam"
adam on Thursday 18 July 2013
"Surround is an organic fungicide made from kaolin clay. The fine particles coat the leaf surfaces and help prevent many diseases."
Barbara Pleasant on Thursday 18 July 2013
"kaolin clay is the same as the white chalky part of kaopectate (the other principal ingredient is pectin). I bought it not as a fungicide but as a deterrent to cucumber beetles, as ours carry bacterial wilt, so it's very important to keep them from feeding. Most insecticides we would use organically would depend on the beetle feeding, and as soon as they feed they can transmit the disease. The fact it's a fungicide and will help prevent powdery mildew on the cukes is a bonus. I got it at gardens alive. They sell 5 pounds for about $30, which would last you a very long time. Amazon lists a pound for $15, which would be plenty for you to try. Most places list it as an insect deterrent, rather than a fungicide. "
lemonfair on Thursday 18 July 2013
"I live Ct. and tried the milk solution 30/60 three applications on consecutive days, on all leaves and it saved plants....all producing without further mildew!"
jeanne on Monday 29 July 2013
"Great news, Jeanne. You must have caught it early. Alert to all -- prevention is better than cure when using any fungicides, including natural ones like milk and water. Take action at the first hint of trouble."
Barbara Pleasant on Monday 29 July 2013
"I understand prevention is better, but I have powdery mildew pretty significantly on my squash and pumpkins.... Is there any hope the milk will kill it? "
Deborah on Friday 9 August 2013
adam on Friday 9 August 2013
"I garden in community gardens, and there is a significant difference in the lack of powdery mildew on my cukes and a neighbor's who sprayed with milk every few days, and others near us who didn't - even one neighbor who sprayed with a fungicide (don't know which one). I had alerted everyone to spray with milk, but perhaps it sounds so improbably easy that they didn't. I'm sold. I even used dry milk once. If you think of how milk dries on a surface, it leaves a little glaze, and I wonder if part of the way it works is that it glazes the leaves so the spores can't grab hold. The milk has not worked 100% on my squash as it has on my cukes, but there is very little mildew. Deborah: If I were you I'd up the proportions closer to 50-50, milk to water. You are not going to hurt the plants."
lemonfair on Friday 9 August 2013
"Once you can see quite a bit of powdery mildew on leaves, nothing will stop it. It's part of old age for cucurbit plants, and as long as the fruits are nearly mature the crop will be okay. There is good genetic resistance in pumpkins, and some PM-resistant varieties of other cucurbits."
Barbara Pleasant on Friday 9 August 2013
"Thanks for the great article! I'm going to try the 50/50 milk solution on my pumpkins, since they are starting to look pretty bad. My question is when to apply it- I've read other places that doing it when it's too sunny could damage the leaves, and that it should be applied early in the morning or in the evening. But, I've read elsewhere that it should be applied in the sun. Just don't want to damage my plants! What do you think?"
Bman11 on Saturday 10 August 2013
"Mild morning sun is the best exposure. Light is part of the chemical chain of events, so some sun is necessary. Midafternoon would be a good second choice. "
Barbara Pleasant on Sunday 11 August 2013
"Whoa whoa whoa. What if my entire crop is already covered? Will this help my plants bounce back??"
Diana on Thursday 22 August 2013
"Diana - According to Barbara three comments up the thread, "Once you can see quite a bit of powdery mildew on leaves, nothing will stop it." But I have found that sometimes new leaves will come along, and you might as well try this on them. "
lemonfair on Thursday 22 August 2013
"I did try the milk spray. I think my plants were too far gone and it didn't seem a cure but I have new growth on the Bee Balm and it seems to be free of it. I will spray with the milk spray to prevent the new leaves from getting it. Its pretty late in the season but maybe I'll have blooms if I protect the new growth."
Wanita on Saturday 24 August 2013
"I read all the comments but I just want to be clear, is it best to use the milk spray as a preventative before any signs of PM or to begin spraying at the first signs of PM?"
Anne on Friday 10 January 2014
"Definitely better to use as a preventive. As Barbara says about 12 posts up the thread, "prevention is better than cure when using any fungicides,""
lemonfair on Friday 10 January 2014
"Well I'm here to tell you that milk works very well on even advanced stages of P.M. My two rose bushes had it so very bad all last year up till recently. I used several different brands of fungicides from the garden center and all I did was throw away money. They worked a little but the stuff would always be right back and they never got rid of all of it. I finally found out about milk sprays. At 50/50 formulation every morning for 4 days straight I sprayed. Its gone! I mean really gone. Not even on the stems where it was the worst. The leaves have a milk coating on them which is drying up now and blowing away in the wind. I have baby cucumber plants showed signs of some kind of icky fungus or what ever. Used powdered milk/water on those. Worked like a charm. I swear they look like different plants today. I truly believe milk is working on more than one kind of plant sickness. I've now used both regular and powdered milk both with excellent results. I'm sold on it. Thank you God for milk. Also any one having problems with over watered plants. Read up on 3% Peroxcide. I've been using that and am totally amazed at the fantastic results on this little jewel as well! "
Ladybat2 on Saturday 12 April 2014
"Powdery Mildew is significant in my "first ever" garden. some leave have even turned yellow. I have trimmed some and am now starting this milk coating I believe it may be too late for mine. I will try this for a week if it doesnt seem to get better I will try to seriously cut back all leaves possibly effected ( this may be significant) in an attempt to salvage them, If tit doesnt help I will pull them up and try again"
Jerry on Sunday 29 June 2014
"How often do you spray ,I have cucumber plants and would a 40-60 solution be good? what the best time of the day to spray? Thanks"
Muriel on Monday 30 June 2014
"Hello, Will this work with UHT milk? Thanks"
Andrew on Thursday 3 July 2014
"Any type of dairy product, including whey (liquid from cheese making) contains the protein that has antifungal properties when it interacts with sunlight. One part milk to five parts water is plenty strong enough, but do use milk spray as a preventative rather than a cure. "
Barbara Pleasant on Thursday 3 July 2014
"Is it too late to do this once the mildew has already started?"
Anne on Monday 7 July 2014
"If you are just beginning to see white patches on a few leaves, a milk spray can slow the spread of the fungi to new leaves. No fungicide will cure powdery mildew once it has become well established. Good luck!"
Barbara Pleasant on Monday 7 July 2014
"I can personally testify that a 70/30 (w/m) spray will significantly cut back even advanced infestations on zucchini, yellow squash and magnolias. Unfortunately the leaves already afflicted didn't heal (the fungus was replaced by yellow spots), but most new growth looks healthy. "
Ben on Monday 4 August 2014
"This is great information! Our zinnias and cukes all have signs of PM and we didn't know how to address it. Live in a small town in IN, have a few veggies growing at the side of the house. My concern was whether the PM will infect next year's plantings in the same soil. What can we do to minimize or eliminate that possibility, if it exists?"
Karen on Friday 3 October 2014
"Will this formulation help on indian basil aswell?"
Nidhi on Monday 12 January 2015
"I have been useing milk two gallons water to one quart milk for fifteen years now and I am here to tell you it works! On grapes, melons, cukes, squash, peas, beets, spinach, tomatos. It also kills leaf curl on my peach trees and fruit trees. It also makes a good fertilizer. Because of it I have a healthy, lush, and totally organic garden."
Mark Wojciechowski on Wednesday 11 March 2015
"Ia am allergic to there any chance the cucumber or squash fruit is absorbing the milk?"
Cheryl on Tuesday 31 March 2015
"Cheryl, as I understand it, the proteins in milk undergo a change when exposed to sunlight. Between that change and the fact that you will not be ingesting milk, I think you are safe. Great question!"
Barbara Pleasant on Wednesday 1 April 2015
"My grapes do have a milk residue on them. So someone with a milk allergy might have a problem here."
mark wojciechowski on Wednesday 1 April 2015
"Thanks very much! I have sprayed my squash leaves today and am hoping for the best. From Cape Town."
Cheryl on Wednesday 1 April 2015
"Hi; I had a 20 yr old tree large flower specimen peonie and moved. I went back to my old house and divided, at least tried to, the plant but only got 1 big main root and 1 main wooded stem.. Unsure if it would live I kept it inside for the winter. Sure enough I saw some leaf growth with a bud on the old hard wood of the plant ; it was a terrible division; wasn't strong enough to do better. Since then I put it outside on my deck in a large pot. All growth was on the old wood, in 1 main old stem; that's it.; however, the buds turned brown and the leaves haven't opened up and grown anymore. The leaves are kind of "stagnant";haven't grown any more;nor have died away; it just stopped. During the winter i noticed white flies and gave it a bit of systemic and they went away. So the few leaves that are on the old wood won't open fully, are stagnant and the few buds turned brown and dry. What can I do to help it prosper? It's a huge flowered specimen peonie; I'd be heartbroken if it dies. PLEASE HELP. Thanks . GOD bless, Elyse "
Elyse on Friday 1 May 2015
"Why don't you try spraying it with milk? Lots of times when I am having any problems in my gardens, milk is a miracle! I would mix an 8 to 1, and spray it hard and also give some of that same mix to the roots. I have your similar problem sometimes starting cuttings of grapes, or on new growth buds on fruit trees. Long before these modern days, I'll bet it was all there was to use."
mark wojciechowski on Friday 1 May 2015
"Also, it does not matter if the milk is organic or commercial, whole, low fat, or non fat. 8 to 1 works just fine. Once a week. It works for just about everything except pests. It brings great health to vegetation. Put some in your bath water if you are having fungal infections. Regular milk works, so it isn't necessary to use raw. For a big garden raw would cost way too much, and it is hard to get. I use about a gallon a week. I get it for free at the local food ministry. Powdered works too, but again, it is expensive. It certainly won't harm any vegetation you spray it on"
Mark WojciechowskI on Friday 1 May 2015
"Can anyone answer my question from October 3, 2014? "
Karen on Saturday 2 May 2015
"Karen, the spores of powdery mildew and all the downy Mildews are simply in the air. They are everywhere! You will never be free from them. Humidity and warm weather escalate thier growth. Half of the fruits and vegetables in gardens are highly vulnerable to it. You have to spray them before they develope, and continue almost weekly. Squash, peas, beets, grapes, apples, pears, cukes, melons, sunflowers, are the worst for me."
Mark WojciechowskI on Saturday 2 May 2015
"Elyse - I'd also look up to see if this might be some botrytis blight you're dealing with, notorious with peonies. And if you think that sounds possible, wood ashes around the base of the plant may help. Karen and Mark - I have seen online some indication that powdery mildew is favored by dry conditions, as counter-intuitive as that sounds (hot dry, in fact, while downy mildew is more favored by humid and cool conditions). It may just be that water washes off the spores from the tops of the leaves, where the powdery mildew tends to arise (downy mildew is typically on the undersides of the leaves). One year one of my community gardeners watered excessively (like 3 hours a day, because he would leave the water running and go off and do other things), and he didn't have powdery mildew on his zucchini at all, while the rest of us did."
lemonfair on Saturday 2 May 2015
"Thank you for such an interesting article. In the UK I am about to put plants into containers to go out (risk of frost for few weeks yet). But will be ready with spray as soon as they put on new leaves as mildew hits every year. It doesn't affect the crop, just looks unsightly and I have to remove some leaves. Strangely, last year the best cropping plants were the two left-overs I planted in semi-shade."
Polly on Thursday 7 May 2015
"Yes lemonfair, hot dry is when my powdery mildew is at it's worst. The reason I mentioned humidity is for rainy areas, and those who overhead water. I live in Georgetown California at 3200 ft. elevation. It is extremely difficult for me to have drip systems on everything.PM is a very big problem. I have grape vineyards. I grow a major amount of winter and summer squash. Major peas. Major cukes. Major beets. Major wheat. Corn. Carrots. Melons. Peppers. Broccoli. Red cabbage. Kale. Spinach. Mustard. Tomatillos. Tomatos. Pirates. Celery. Plus all the fruits in my orchards. I grow no herbs or flowers. If I can't eat it I don't grow it. My ancestors come from Poland. Used to be the breadbasket of Europe. Us Poles have green thumbs. My grandpa and father both had huge gardens, and my sister and I both grow most of our own food. I am retired now 65 and took in my gardens all day every day. It's just me and my there dogs now. Iam very successful. Totally organic. No poisons allowed here. Living in harmony with all my birds, bugs, miles, and spores. My soils are all biogenically alive. I eat mostly raw foods and juices. Am extremely healthy. The easement gospel of peace is my religion. This website can be a took for similar folks. My email is"
Mark WojciechowskI on Thursday 7 May 2015
"The Essene Gospel of Peace is my religion. This website can be a great took for similar folks. I invite you to talk to me directly at my above email. Mark."
Mark WojciechowskI on Thursday 7 May 2015
"Have you tried milk/water spray on peas."
Rosa on Sunday 17 May 2015
"Yes Rosa. It most definitely works on peas. Once a week. 1 part milk to 8 parts water."
Mark WojciechowskI on Sunday 17 May 2015
"Does it matter if milk is old or slightly sour (not curdled)? Might be able to get it for free that way."
Denise on Saturday 23 May 2015
"Aged milk will be fine as long as it has not clotted, which will clog up a sprayer. The necessary proteins are present in whey, so I suppose you could use clotted milk if you strained it through a fine cloth first."
Barbara Pleasant on Saturday 23 May 2015
"So, what this milk spray is really all about, is not just the fact that it kills powdery mildew and downy . And, also brings health and vitality to every plant you spray it on. It has always been used throughout history for such things. It is relatively new in America, but old as life in the world. Here in America, chemicals are the rule. Sulfur has always been used here.And people are convinced it is ok, because your body needs sulfur.Yes, your body does but it needs "organic" sulfur, which comes from plants , like beets. Commercial sulfur are mined. It is the same sulfur used in road flares and matches and fireworks. Is is highly poisonous and toxic to the human body. It is inexpensive compared to milk. Unless you have your own cows. These chemicals are why Americans have the greatest cancer and disease rate in the world. Personally, I choose health, is why I choose milk."
Mark WojciechowskI on Saturday 23 May 2015
"It only costs me a gallon of milk a week. $3.50."
Mark WojciechowskI on Saturday 23 May 2015
" is a very interesting site! Everybody should look there. I think I still prefer milk. "
Mark WojciechowskI on Wednesday 27 May 2015
"Most comments mention spraying. Sprayer hooked to a hose or separate pressurized container with spray nozzle?"
Bangel on Saturday 30 May 2015
"Bangle. Separate pressurized container."
Mark Wojciechowski on Saturday 30 May 2015
"One neighbor commented that they also powder the egg shells and put them at the base of all their plants in the garden and tha reduces the disease. "
Lexy on Saturday 6 June 2015
"I hate to use pesticides unless extreme measures are needed so I was really grateful for this site. Milk is now my one true love, to drink and keep 'anything' that can or does suffer from powdery mildew under control/eradicated! I've had total success on everything from beetroot leaves, cucumbers, beard tongue and even roses! Got to love organic gardening it's the best way to go."
Song on Wednesday 17 June 2015
"Just to let everybody know, I have officially increased my milk to water ratio from years of one part milk to eight parts water to 1.5 parts milk to 8 parts water.Much better. Just right."
mark wojciechowski on Tuesday 23 June 2015
"Now I need to get a milk goat. That way I have milk all the time. I met a Russian family here and they had a milk cow. Giving them 5 gallons a day!. I will settle for goats. Raw goat cheese too. Raw butter too. I spray half of my huge garden twice each week. Takes 2 gallons per week. I need milk. Goats!"
Mark Wojciechowski on Tuesday 23 June 2015
"I wonder if the milk is feeding beneficial baceria like lacto Baccillus that then out competes the milldue. Perhaps the sulphur properties in garlic would also help in the spray...."
Ian on Thursday 9 July 2015
"I am working on a project to make a model on prevention of Downy Mildew in South Australia.I would really be thankful if someone has any information on which month downy mildew prevailed. Dec 2010 was one of the month according to my survey."
yc on Monday 3 August 2015
"Prevailed??? I have been farming all my life, and powdery mildew has shown up on my grapes, squash, peas, cukes, beets, carrots, ect. for all of my 65 years. And, just for the record, I have adjusted the mixture (again) to 1 qt. milk, 1 gal. water. I find that it also helps to lightly pressure wash before spraying the milk . As far as one year starting it? I don't see that.It has always been here, and it will always be here."
Mark WojciechowskI on Monday 3 August 2015
"Or one month being any better or worse? By December here in California mountains 3200 feet elevation, it is all over. Winter has set in. My growing season here is march through November. It shows up from day one until the end."
Mark WojciechowskI on Monday 3 August 2015
"YC, downy mildew is very different from powdery mildew. In your research, begin by checking with plant pathologists in AU for the correct species name, probably Phytophthera or Pythium, and its specific plant association."
Barbara Pleasant on Monday 3 August 2015
"Ah, but milk works for all Mildred!"
Mark WojciechowskI on Monday 3 August 2015
"I live in Devon, UK, which is mild and damp and always have a battle with potato blight. I read an article about lacto-bacilli cultures and gardening and decided to give it a try. Method: collect some of that yellowy watery stuff from live yoghurt (in my case it was from home-made kefir) put it into a bottle with a screw top, add a little sugar and shake up. Leave for several days with top loose enough to allow fermentation gases to escape. I then added some rain water (boiled and cooled tap will do as that drives off the chlorine) After a few days it will smell yeasty but not unpleasant. I then put a small amount into one of those cheap plastic misters and topped it up with rainwater again (very unscientifically I didn't measure! but a mister bottle full of water had about 150ml of ferment in it) The remaining ferment had another feed of sugar. I sprayed my potato plants topside and underside of leaves just the once, my father's potatoes in the next bed unfortunately I used as a control (he doesn't care for my experiments!)Result was Dad's bed all had to be cut down as usual, mine were, and remain,free of blight! The reasoning behind this is the "friendly" bacteria have a head start on the plant and then outcompete any bad ones. Could this be why you have to repeat spray just with milk because there are only a few of the lactobacilli in fresh milk? Love to hear anyone else's thoughts. Definitely trying it on courgettes next year."
Sue Hepworth on Wednesday 12 August 2015
"This sounds brilliant Sue. I have given up planting potatoes for two years now because of blight but will give this a try next season."
Brenda Jones on Saturday 15 August 2015
"Remember as in most home-remedy's they work better as a preventative rather than a cure. Most of the fungal diseases are difficult to control once established and thriving. Catch it early."
Ian on Monday 17 August 2015
"Like this site... What about aphids...Hate them. What works best to keep them of my plants?"
roger on Wednesday 30 September 2015
"Hi Roger, we have an article about aphids that you might find interesting:"
Ann Marie Hendry on Wednesday 30 September 2015
"One or two tblspns of Dr Brommers peppermint soap in one gallon of water. Will kill the aphids without harming your plants. Or any dish detergent. But I use organic liquid castile soaps."
Mark WojciechowskI on Thursday 1 October 2015
"just curious i have hybrid tea rose elina recently bought them and have notice some mould on a few leaves, how often do i need to use the milk spray?"
cate on Sunday 8 November 2015
"Cate, if you are seeing only a little powdery mildew on your Elina rose, simply clip off the affected leaves. Next year, give your plant light milk sprays starting in midsummer, every 2 to 3 weeks, because prevention works better than cure with powdery mildew."
Barbara Pleasant on Monday 9 November 2015
"Here in Queensland, I've been losing my Spanish melon and nudie pumpkin to powdery mildew, maybe not too late to save them. Thanks Mark for your tip as well."
Dana on Saturday 9 January 2016
"I think Sue has hit the nail on the head, the good stuff "Lactobacillus" is in the whey and out competes the bad bacteria, vermicast mixed with water and molasses has a similar beneficial effect on controlling problem causing microbes. If one alternates each week BEFORE the problem has set in then you can keep on top of the situation with healthy plants. . . . Ian C "
Ian C on Thursday 4 February 2016
"Ian, it is not about bacteria or fungi v fungi. Proteins in the milk interact with sunlight very briefly to create a disinfectant effect. "
Barbara Pleasant on Thursday 4 February 2016
"when I was 5 or abit older I remember watching my mother clean the house plants with milk it also makes the leaves shine after removing the dust that had settled on them after cleaning the house. will try on plants outdoor like the winter squash Thank You! "
Valerie on Wednesday 1 June 2016
"Are you using whole milk? Skim? "
Kathy on Friday 24 June 2016
"Use any type of milk, Kathy. It's a protein in the milk that does it, so some grape growers even use whey, the watery by-product from cheese-making."
Barbara Pleasant on Friday 24 June 2016
"I have modified my recipe for using milk on my grapes . I was using 1 quart of milk in 2 gallons of water. But was still getting mildew badly. Now I mix 1/2 gallon of milk in 1 1/2 gallons of water. Don't skimp on the milk! I have no mildew this year!"
Mark WojciechowskI on Friday 24 June 2016
"Thanks guys will give the milk treatment another go. regards, Stewart."
Stewart on Sunday 17 July 2016
"I want to point out that the picture that you have used at the top of the page does not have powdery mildew. That is a picture of Cushaw squash and they naturally have white spots in their leaves like that. However, they can get powdery mildew and the leaves turn more of a blueish color. I am fighting that right now. But, that is not a good example to show people."
Kayo Parsons-Korn on Sunday 31 July 2016
"Good point, Kayo. Do you associate the silver streaks in the leaves with cushaws? The squash shown is tromboncino, which I've always thought was c. moschata. This year I have two plants that are supposed to be moschatas that are showing the silver pattern, so I'm curious."
Barbara Pleasant on Tuesday 2 August 2016
"Yes, just do a search on Cushaw Squash Plants to look at a few images and you will see that the silver streaks/spots on the leaves is just how they look.I just goggled Tromboncino squash and it looks like they do too. Although the pictures I saw of them were not as pronounced as on the Cushaw. I knew I had mildew because the leaves were actually turning a whitish/blue over the entire leaf. Its interesting that you mention that they are c.moschata. Bill McDorland, a well known seed saving expert, thought he was seeing crosses between Cushaws which are c.mixta with c.moschata. I do get some Butternuts that have more of a Cushaw shape. So maybe they can cross. By the way, I tried the milk and so far so good. But I plan to buy a gallon of some cheap milk as my husband needs the lactose free which is much more expensive. I will have to apply the milk mixture often as our monsoon season (Arizona) seems to be in full swing. Thanks for the good article. "
Kayo Parsons-Korn on Tuesday 2 August 2016
"Thanks to the eagle-eyed readers who spotted that the first image on this page showed a squash with variegated leaves, not powdery mildew. We've replaced the pic now. "
GrowVeg on Wednesday 3 August 2016
"I have regular deliveries of goats milk and wonder if it is just as effective as cows milk as a powdery mildew preventative for my courgettes. Please can you let me know."
Ann Lindsay on Wednesday 31 May 2017
"Ann, nobody knows the answer to your question because cow and goat milk have not been compared in field trials, but gardeners who have used goat milk just as they would cow's milk report good success. This would be a good use for small amounts of stale milk. Good luck!"
Barbara Pleasant on Monday 5 June 2017
"My spaghetti squash started showing spots of powdery mildew on a couple leaves few days ago. I removed the infected leaves and sprayed (soaked really) that plant, all plants in a 2 foot radius, and then all plants in the entire garden that are vulnerable to powdery mildew. Used a 40:60 ratio of whole cow's milk and water in a pump sprayer. Applied in bright sunlight and there was no smell. I haven't seen any mildew since and this fungus typically spreads fast - from my previous experiences where it has consumed all my squash. Since this is such a cheap solution I will continue to use it every 10 days."
Annie on Tuesday 20 June 2017
"My grapes get mildew every year. Last year I treated with a shop-bought product and the grapes were nonetheless too affected to eat. This year I started spraying with 25% UHT milk, 75% water and it's working really well. As soon as I saw signs of mildex, I sprayed the whole vine every 2 days for a week. The mildew completely disappeared for about a month. It's now come back so I'm starting a new course. This time last year, my grapes were white and pretty much lost. This year they're doing really really well so I would definitely recommend!"
Claire on Friday 21 July 2017
"So I don't have any animal milk on hand. I drink almond milk. I mixed it up with water and sprayed this morning. Any idea if it wil work the same? I'll let you all know. :)"
Chelsi on Thursday 10 August 2017
"Does diluted milk work as a fungicide for other fungal diseases or is it exclusively effective for powdered mildews?"
Anne Marie on Saturday 19 August 2017
"Chelsea, the proteins are very different in almond milk, so I would not expect the same results as with dairy products. Anne Marie, to my knowledge powdery mildew is the only fungal disease group that is clearly impacted by milk sprays. "
Barbara Pleasant on Saturday 19 August 2017
"If spraying milk could prevent powdery mildew what about Downey mildew? Cos I have tried all effort but proved futile in treating DM... Can i spray milk for DM?"
Saheed on Saturday 25 November 2017
"Saheed, there is no research to support use of milk spray on downy mildew, but you could try it as a preventative. The problem is that dampness contributes to DM, so spraying anything could make problems worse. With some vegetables there is genetic resistance, but no resistant varieties of cucumber family crops exist at this time."
Barbara Pleasant on Monday 27 November 2017
"Hi from France, My green house grape vines have suffered from mildew for the past 4 years, I've tried copper fungicide with no luck so this year I'll try the milk treatment as you say Barbara all I'm going to lose is a carton of milk over the season, wish me luck. Cheers, Ken Smith "
Ken Smith on Thursday 22 February 2018
"60/40 water milk spray worked like magic on my large rose bush. Within hours the mildew leaves sprayed were glossy and green. I keep the milk water mix in spray bottle in fridge. I've been retreating 2Xs week for past 2 weeks and mildew is greatly reduced. I'm sensitive to odors and there has been NO spoiled mild smell. I had used commercial fungicide a month earilier with little to no improvement. With the milk water mix, I don't think I need to worry about harming bees. "
Mischa on Saturday 16 June 2018
" Enjoyed the article on milk spray by Barbara. Thank you."
Stewart on Wednesday 27 June 2018
"I have a squash-like plant with large, round, variegated leaves with no sign of pm yet...I'll try the milk treatment and report. The flowers are large and yellow. Anyone know what the plant is?"
Robert Fulton on Friday 3 August 2018
"I carefully followed this advice and the advice from commenters on the milk to water ratio but the problem continued to worsen and my pumpkin vines died last summer. "
Teri on Friday 31 August 2018
"Thanks for the update, but no one answered my 8/3/2018 question...could it be butternut? And, why ask for my email address for this reply? You sent this email to me and I had sent it when I initially asked the question. What are computers for?"
robert fulton on Saturday 1 September 2018
"Robert, a rounded leaf with silver variegation is usually a C. moschata such as 'Black Futsu'. Most regular butternuts lack variegation, but you never know. Some C. pepos have variegation, too, but their leaves are more pointed."
Barbara Pleasant on Sunday 2 September 2018
"When I spoke to the owner about powdery mildew on my new peonies, she recommended a mild bleach solution for the soil. I see nothing about that on this website. What would be the proportion of bleach to water? Has anybody heard of this?"
Haller Helga on Friday 19 October 2018
"HH, powdery mildew of peonies seems to be an increasing problem, but rather than using bleach you might try neem oil used as a preventive. I don't know that milk has been tried on this strain of powdery mildew, but it could be worth a try. Cleaning up withered leaves at the end of the season can reduce problems next year, too. Good luck! "
Barbara Pleasant on Monday 22 October 2018
"It has to be skimmed milk because the butter clogs the mouth of the leaves and instead of curing them, we suffocate them."
Peho on Thursday 23 May 2019
"Do you think that UHT milk would work?"
Nick Wright on Monday 15 June 2020
"Nick, it as recommended in this thread, go for it! Even using spoiled milk filtered with sieve or some porous cloth."
Vicki H. Burt on Monday 21 September 2020

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