Preparing Perennial Herbs for Winter

, written by gb flag

Drying herbs indoors from winter prunings

Some of the most popular herbs are both perennial and evergreen, which makes it tempting to let them do their own thing. Oregano, thyme, sage and lavender are all very easy to neglect when there are so many other things clamoring for attention but this is exactly why at one moment they can be compact mounds of aromatic delight and then, seemingly a moment later, an unwieldy sprawl of woody stems.

I inadvertently left an English lavender untrimmed for several years early in its life, and it now has a forest of bare stems at its base. (Yes, I know all the textbooks would have me grub it up and start again, but it’s so matronly that I keep it. It’s also a constant guilt-trip that makes me pay attention to all the herbs that might go the same way.)

Preparing Sage, Oregano and Thyme for Winter

This time of year is a good time to sort through the sage, oregano and thyme, cutting out any dead wood and extracting weeds that have grown around their base. Most importantly, trim off the dead flower heads to help keep the plants bushy. Don’t trim too low down the stems (a light trim of the top leaves is enough) as the plants need time to recover before the cold weather arrives and small tender shoots engendered by fierce pruning won’t take kindly to being bathed in frost.

Trimmed sage bush
A sage bush after seed heads have been removed for its winter trim

Trimming the plants also gives you a chance to dry the pruned-off leaves, removing the need to trek down the garden in the depths of December to gather a bouquet garni. One of the easiest ways to dry herbs is to peg individual sprigs to a line strung up somewhere warm and dry, until the leaves are ready to crumble. Then store in air-tight containers.

Although sage, oregano and thyme will provide leaves over winter without protection, you should check their growing guides in case your winter temperatures are so low that small plants should be potted up and taken indoors. Fleece can help protect larger plants and, even in more temperate climes, you might think it worth throwing some fleece over them in winter to obtain a greater supply of larger, more tender leaves.

Rosemary can be trimmed in winter or you can wait until spring. For details, see our article on The Worst Enemies of Rosemary.

Overwintering Bay Laurel

One herb that must be protected in all but the most sheltered positions is the bay tree. Bay trees really don’t like being frozen and, caught out by the sudden arrival of snow, I kicked myself last year for not rushing out to protect my treasured lollipop-trained specimen. Mulch bay trees with compost to protect the roots from frost and, when the cold weather threatens, wrap the plant itself in fleece. If the worst happens and a ground-planted bay seems to have been killed off, it’s nevertheless almost certainly going to shoot up again from the base when spring arrives, as the roots will have been protected in the ground. The same cannot be said of pot-grown bays, however, as the freezing temperatures will have penetrated the roots. To avoid this, pots should ideally be moved indoors or, if too heavy to move, swathed in bubble-wrap, while the top growth is again protected with fleece.

A bay tree resprouting after being killed by frost
A bay tree resprouting after being killed by frost

Preserving Mint

Mint is a perennial that will begin to die off soon and it’s often recommended that you pot up mint to take indoors for winter use. I’ve tried this a couple of times and, to be honest, it didn’t really work; the mint got all straggly and miserable and died off anyway. Further research revealed that mint seems to need to fall dormant for a period, so that explains why. If you do want to preserve mint for cooking over the winter months, it’s better to harvest clean, fresh leaves now, chop finely, pack into ice-cube containers, immerse thoroughly in water and freeze.

Fennel Seeds

Another favourite perennial, fennel, also dies off for the winter. By the end of summer it will be carrying seed heads on stately stalks up to around five feet high. If, like me, you have a relaxed view of weeds, you might like to let fennel stand over winter as the skeletal seed heads make an attractive winter feature. However, fennel self-seeds with aplomb and, if you don’t spot the tiny shoots early, they can put up a bit of fight when you try to pull them up. To avoid this, cut down the stalks before they get the chance to chuck the seeds around. Alternatively, place a bag over a seed head or two in order to catch the ripe seed when it falls, and gain a supply for curries and stews or to sow next spring.

By Helen Gazeley

Bugs, Beneficial Insects and Plant Diseases

< All Guides

Garden Planning Apps

If you need help designing your vegetable garden, try our Vegetable Garden Planner.
Garden Planning Apps and Software

Vegetable Garden Pest Warnings

Want to Receive Alerts When Pests are Heading Your Way?

If you've seen any pests or beneficial insects in your garden in the past few days please report them to The Big Bug Hunt and help create a warning system to alert you when bugs are heading your way.

Show Comments



Comments

 
"How timely! Just this morning I spent good hour or so outside cleaning up my vegetable and herb gardens. I also planted my garlic and cut back the asparagus fronds to neaten things up at that end of the garden. I have bunches of rosemary (vulgaris and Mrs. Howard), tri-color sage, pineapple sage and plain sage hung up in the attic to dry. I already have quantities of oregano, thyme, savory and basil dried and bottled. Just before Thanksgiving I enjoy gifting my friends and close neighbors with fragrant dried herb bouquets to use in the holiday feast preparations. It is a real pleasure to share something from the garden! "
Denise on Tuesday 27 September 2011
"Hi, Denise. That all sounds lovely and I agree, there's something deeply satisfying about giving away stuff you've grown yourself and herbs are a lovely fragrant gift. How do you find the dried basil, though? Do you find it keeps its flavour?"
Helen Gazeley on Tuesday 27 September 2011
"Hi Helen, This article was very helpful to me as it cools down here in Va. Beach. Can you give more details on the kind of fleece we should use to protect the herbs? This is the first time I had heard of it. Thank you!!"
Melody on Friday 7 October 2011
"Hi, Melody Fleece is a thin, very slightly furry fabric made of spun-bonded polypropylene, generally available in a standard weight (17g here in the UK) which protects plants down to minus 2-3 degrees Centigrade (28.4-26.6 degrees Fahrenheit) and heavyweight garden fleece (30g), which protects plants down to minus 5-6 degrees Centigrade (23-21.2 degrees Fahrenheit). It is now possible to get biodegradable fleece, which should compost when it reaches the end of its life; I haven't tried this but you can see more at http://www.wmjames.co.uk/biodegradable-horticultural-garden-fleece-12m-x-100m-roll-g401b.htm. If anyone has a link to a provider in the US, let us know. "
Helen Gazeley on Friday 7 October 2011
"I wonder if "fleece" is the kind we can find in the fabric stores around here in the USA? Or if it is like interfacing - also found in fabric stores? How does one use it? Do you drape it over the plant or stake it around the plant, or...?"
Terri MP on Saturday 8 October 2011
"In the US fleece is often called 'garden fabric', floating row cover fabric or similar. Many online gardening stores stock it, for example: http://www.gardeners.com/Row-Covers/5111,default,pg.html"
Jeremy Dore on Monday 10 October 2011
"Can a pot of spearmint growing out doors remain out during the WY winter and will it survive?"
Dennis Becker on Monday 3 October 2016
"Spearmint is very hardy - down to about zone 4, so probably fine in WY. That said, it is in a pot, so there is a danger that the extreme cold could harm the roots. If you can, move the pot to somewhere sheltered and perhaps wrap the pot up in bubble wrap, burlap or fleece row covers to protect it a little."
Ben Vanheems on Thursday 6 October 2016
"Just read Helen's comment about "cutting back asparagus fronds to neaten things up". This is our 1st year growing them in Virginia Beach. Should I cut back in preparation for frost in November? "
Melody on Thursday 6 October 2016
"I have English lavender outside, I have zone 5 soil. Would I need to cut it down before winter? Or just leave it go? I live in Northeast , Pennsylvania. "
Wanda on Monday 10 October 2016
"Hi Melody. You can cut back asparagus fronds as soon as they have withered/turned yellow or brown. They naturally die back in the fall/autumn, so essentially you can cut them back whenever you want after this point. This is usually about November."
Ben Vanheems on Tuesday 11 October 2016
"Hi Wanda. English lavender is hardy up to zone 5, so should be fine in Northeast Pennsylvania."
Ben Vanheems on Tuesday 11 October 2016
"You forgot basil"
opinion on Sunday 30 October 2016
"I found this really helpful. I have been wondering how to keep my thyme over the winter in S. Ontario. I'm either going to move it from the planter to a spot in the ground with extra soil and mulch or wrap the planter with bubble wrap and/or burlap. Thank you!"
DebJane on Saturday 3 November 2018
"I have potted chives that during the winter, I place under a sheltered part of our deck and it comes back each year. Can I do the same with potted mint and thyme?"
Bonnie S on Friday 9 November 2018
"Yes, that should certainly be possible if this tactic is working for your chives. The key thing is to make sure they never get waterlogged in their pots, which is often more fatal than the cold. Check they have adequate drainage and won't be standing in pools of water where you plan to overwinter them."
Ben Vanheems on Monday 12 November 2018
"Thanks for the article. But just another of many from regions that don't know what winter is. We've already had a few killing frosts in Alberta; winter can hit anywhere from October to December, last through April or May, bring prolonged 30-35 below Celsius, and also freeze/thaws from chinook winds over the Rockies - if we're lucky. I'm thinking of cutting back my perennial herbs and burying in mulch (e.g. pea vines), and sinking the one foot pots into the ground before mulching. But the search continues for an answer. Happy gardening, Be well. "
GE on Tuesday 22 September 2020
"It sounds like you have some pretty sever winter weather to contend with - fresh to say the least! I think good, thick mulch could certainly help insulate your herbs against the most severe effects of the cold, so it certainly worth a try."
Ben Vanheems on Tuesday 22 September 2020
"I would like to keep my peppermint and cocoa mint over the winter. I live in the St. Louis, MO area (zone 6a). I am thinking about putting the potted plants in a tub with mulch . My question is, should I cover the pot with a fleece blanket? I would like to keep it next to my house in the back yard. Will it need to be watered during the winter?"
Anita on Friday 9 October 2020
"Hi Anita. Mint is pretty hardy, and will do just fine outside where you live. The plants will naturally die back then re-sprout and grow again in the spring. If you want to keep plants going over the winter, you could dig up and split the plant, potting some of it up in potting mix to bring indoors to a bright windowsill. You may continue to get fresh leaves. Or if you just want to overwinter your pots and you are worried about very severe frosts, you can simply bring them close to the house where it will be a little warmer. They shouldn't need covering or mulching, and the rain/snow that naturally falls should be enough to keep plants ticking over till spring."
Ben Vanheems on Monday 12 October 2020

Add a Comment

Add your own thoughts on the subject of this article:
(If you have difficulty using this form, please use our Contact Form to send us your comment, along with the title of this article.)

 
   
(We won't display this on the website or use it for marketing)



Captcha


(Please enter the code above to help prevent spam on this article)



By clicking 'Add Comment' you agree to our Terms and Conditions