Mulch on top of herbs over winter

Rick7072(6b)November 10, 2012

I'm here in eastern Massachusetts in Zone 6b. I have a few thyme, oregano and marjoram plants outside that I'd like to keep harvesting from occasionally during the winter. I've heard that I have the best chance of making that happen if I cover the plants with a thick layer of mulch, so I now have some salt marsh hay for that purpose.

But I'm wondering if I should completely cover the plants with several inches of hay during the winter. I'm sure it would be warmer for them that way, but I'm worried that it would completely block out any winter sunlight that I would imagine they would need to keep the leaves green. I can't imagine that photosynthesis completely stops during the winter, or does it?

Any advice on this? Thanks.

Thank you for reporting this comment. Undo
fatamorgana2121(Zone 5/6)

I can't imagine any of these plants would continue to produce throughout the winter for you in such conditions. They wouldn't here and I'm only slightly colder since I'm technically zone 6a. You might be able to extend the season some with a cold frame or a cloche, but there are limits to that. And yes, if you want to harvest from the plants, photosynthesis is needed since it is the green leaves you are intending to harvest.

What is the zone hardiness for marjoram? I think that one may be too tender for your zone. I know it is for mine.


    Bookmark   November 10, 2012 at 2:20PM
Thank you for reporting this comment. Undo

Thanks. I've seen several articles on the web suggesting that you can continue to harvest from oregano and thyme even during the winter if you put a thick mulch on top. Here's one:

The author Gail Reynolds writes:

"Covering your herbs with a heavy layer of straw can buy you months of continued harvest"

And later: "Simply lift up the straw cover, gather yourself a handful of the herb of your choice, and reposition the covering. Done deal."

But she does say that she is using this technique in the fairly moderate climate of southwest Missouri, which certainly has warmer winters than Boston.

Well, I guess I'll experiment and see what happens. I'd be curious to know if anyone else has done this in Zone 6 or thereabouts.

    Bookmark   November 11, 2012 at 10:27PM
Thank you for reporting this comment. Undo
flora_uk(SW UK 8/9)

In a region with wet winters, mulch on Mediterranean herbs would be death. You're even recommended to keep fallen leaves from them. They need air circulation. However, if you have cold, dryish winters it might be OK.

    Bookmark   November 12, 2012 at 5:30AM
Thank you for reporting this comment. Undo
fatamorgana2121(Zone 5/6)

I agree with Flora - I think such mulching would mean sure death in my winters for these plants. Or at the very least, all the above ground portions of the plants would be lost to the mold and rot such a covering would do. I can't imagine much different results in other Northeastern US locations.


    Bookmark   November 12, 2012 at 9:49AM
Thank you for reporting this comment. Undo

I grow common thyme and lemon thyme in the ground in zone5b without mulching it. But oregano and marjoram, I have to grow them in the pot and move them in the garage for the winter. They will not survive winter outside here.

    Bookmark   November 12, 2012 at 12:47PM
Thank you for reporting this comment. Undo

Thanks for all the advice and I'm really glad I asked this question. As I read various articles on the internet about winter mulching, it looks like maybe the idea is to mulch *around* the plant so as to maintain uniform soil temperatures around the root and therefore prevent the ground from heaving from freezing and thawing, rather than to keep the plant warm which is what I originally thought.

In that case I wouldn't put the mulch on top of the plant (though that one article I mentioned does seem to suggest doing that -- though maybe I'm misreading it).

And maybe the thyme will be fine unmulched but not the oregano. I'm hoping the oregano will at least survive my 6b winter if not keep its leaves green. Whether either the thyme or oregano will remain green during the winter is anyone's guess, but from what folks are saying I shouldn't be surprised if they don't.

    Bookmark   November 12, 2012 at 8:20PM
Thank you for reporting this comment. Undo
gjcore(zone 5 Aurora Co)

Thyme and oregano should survive the winter but I wouldn't expect much growth from mid November to mid February.

If the plants are big enough now you could try drying some for winter use.

    Bookmark   November 12, 2012 at 8:30PM
Thank you for reporting this comment. Undo

Thanks, GJCore. Even though I shouldn't expect much growth from mid-November to mid-February, do you think it's possible the oregano and thyme leaves might stay green and harvestable during those months?

    Bookmark   November 12, 2012 at 11:21PM
Thank you for reporting this comment. Undo
fatamorgana2121(Zone 5/6)

Oregano survives here in the snow, cold, and ice of Western NY State. I mulch nothing. Sage, thyme, english lavender, oregano, roses, etc. all survive with no problems. Drainage is key to winter survival. Pooling water = death. Of note, I was originally zone 5 and rezoned in the last zone map updates to 6a so oregano (Origanum vulgare) should survive your 6b with no problems.


    Bookmark   November 13, 2012 at 8:07AM
Thank you for reporting this comment. Undo

Thanks, fatamorgona. That's great news that the plants survive through the winter. I'm curious if the leaves of thyme and oregano stay green and harvestable during the winter?

    Bookmark   November 13, 2012 at 8:49AM
Thank you for reporting this comment. Undo
fatamorgana2121(Zone 5/6)

Oregano dies back to the ground. Thyme retains its leaves but the plant goes dormant and often looks more purple than green through the winter. So no and no.


    Bookmark   November 13, 2012 at 2:59PM
Thank you for reporting this comment. Undo
flora_uk(SW UK 8/9)

Even here where they all stay green I find the flavour less strong in winter.

    Bookmark   November 13, 2012 at 4:23PM
Sign Up to comment
More Discussions
plants in cat litter bags?
I've seen pics of plants growing in reusable shopping...
What is attacking my basil? Whiteflies?
I have an indoor growlight which has allowed me to...
banana and lime mints
I would love to hear from anyone growing these and...
Herb Seedlings Yellowing - Basil, Oregano, Chives
I just started some herb seeds and was wondering if...
Urgent Rosemary Help!
A family member bought me a beautiful rosemary plant...
Sponsored Products
Dusk Blue Double Gourd Table Lamp
$99.99 | Lamps Plus
Barclay Products Bathtubs 5 ft. Cast Iron Roll Top Bathtub Kit in White with
Home Depot
Cameron 6 Drawer Media Chest - Traditional Cherry Multicolor - CM750TV
$710.00 | Hayneedle
Pastel Ellejoyce Club Chair - Chrome - Top Grain Red Leather
Beyond Stores
Allergen/Water Resistant Mattress Pad - Queen
$39.00 | FRONTGATE
Bronze Contempo Lamp Candle Warmer
$22.99 | zulily
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™