how to store garden vegetables for winter

WE TALKED ABOUT storing tender ornamental plants recently, but what about garden vegetables, now that colder nights and days are here? Each year I need to remind myself what stores best where—which is most of all determining what particular combination of temperature and humidity, such as cold and moist versus cool and dry, and so on. It also takes some experimentation, since our modern homes tend to lack just the perfect place. (Oh, to have a root cellar!) How to store homegrown garden vegetables.

temperature and humidity

MOST VEGETABLES prefer to be stored at 32 to 38 degrees F.  Notable exceptions: sweet potatoes (55-60 degrees), and pumpkins and winter squash (50-55, after a week or two curing even warmer). Many also like it humid (root vegetables and potatoes, for instance—like 90 percent or thereabouts), but others such as onions and garlic and winter squash won’t do well where humidity is so high. By the way: Home refrigerators are usually cold and dry (40°F and 50-60 percent relative humidity), says the University of Minnesota Extension, in their thorough bulletin on vegetable storage.

Various extension services and other experts, such as the Maine Organic Farmers and Gardeners Association, have extensive recommendations, often with charts to simplify things (this one’s from MOFGA, part of a comprehensive pdf):

the basics of storage

VEGETABLES AT PEAK maturity will store better than underdeveloped or over-ripe ones. Delay harvesting as long as possible, presuming it doesn’t mean the vegetable is deteriorating, or animal pests are apt to be gnawing at it.  Root vegetables can enjoy a little or a lot more time in the ground if your garden is pest-free; kale and collards and Brussels sprouts can stand into the frost awhile.

Harvest carefully–don’t bruise or handle things roughly, and set aside any nicked or otherwise imperfect produce to use up first. That includes immature things that might be good enough to use in a soup or other dish right now, but won’t keep. For example, I make soup from any bruised potatoes as soon as they are dug.

Some things don’t store well no matter when you harvest—tomatoes and peppers, for instance. Freeze peppers at their peak, instead, and tomatoes, too, or cook them up into some delicious concoction that cans or freezes well.

One more basic: There’s no substitute or remedy better than growing a storage variety in the first place. So, for instance, I eat all my ‘Ailsa Craig’ onions first (not meant to keep) and store my ‘Copra’ ones (a rock-hard keeper). Among the species of pumpkins and winter squash, those in Cucurbita maxima (including ‘Blue Hubbard,’ and ‘Lakota,’ ‘Jarrahdale,’ ‘Buttercup’ and many more) are generally the best keepers. Nothing you can do to make a summer squash last all winter! You get the idea. Choose varieties at seed-shopping season with storage in mind.

extra details by crop

FOR TEMPERATURE and humidity ranges, refer to the chart above or the one below (copyright 1996 by the University of Wisconsin), which is part of a great vegetable-storage factsheet by H.C. Harrison that also includes details about indoor storage room details, outdoor pit-style storage, and more.  Some extra tips, besides the temp and humidity particulars:

squash and pumpkins: Though different species are better or worse keepers, the general idea: Cut fruits from the vine, leaving stems intact, after the stem is getting corky or at least woody, and the skin is hard and may be starting to dull. Slightly immature fruits may continue to ripen off the vine, so long as they are not stemless (I leave a piece of vine attached at first, too.) Most need a week or two in a warm, dry, airy spot (about 75-85 degrees) to cure. Don’t let these guys get cold (below 50) once they are cured.

root vegetables (carrots, beets, rutabaga, parsnips, turnips): Leave in the ground as long as possible, perhaps with straw or leaves as mulch on top to insulate.I have friends who dig theirs gradually, well into winter, by mulching enough to keep the ground unfrozen. When you must dig, trim tops short (without removing the top of the root), cooking the bonus crop up where possible (such as beet and turnip greens). I then store these in the crisper drawers of my refrigerator for the remaining months of winter, which is not really humid enough, but I somehow make do.

potatoes: Harvest after vines die down, then cure at 50-60 degrees for a couple of weeks (avoiding light) before moving to cooler, humid storage. Maine Organic Farmers recommends wrapping each cured tuber in newspaper before putting them in storage bins or baskets.

sweet potatoes: These are hard to store (and even harder up North, where we get fewer truly mature tubers that are ideal for keeping). Curing fresh-dug sweet potatoes will help their skins firm up, allow any nicks to heal, and also give them time to get sweeter, converting inner starches to sugars. Louisiana State and elsewhere recommend 5-10 days at 80ish degrees after digging and similarly high humidity, before storing around 55 or 60.

garlic and onions:  I grow a year’s worth of garlic from my own “seed,” harvesting in August or thereabouts, and drying in a warm, dry spot (but not in the sun) for several weeks before trimming the roots and tops, and storing cool, dark and airy.  I also freeze some garlic and onions for use next spring and summer, when it would have begun to sprout in storage.

herbs: I freeze mine in a variety of concoctions. How to freeze herbs.

other crops: Refer to the charts, or better yet, click the links to the Maine Organic Farmers and Gardeners pdf, the Minnesota extension website, or the one from University of Wisconsin, with its added bonus of dreamy storage-room plans. Some day!

university of wisconsin vegetable-storage chart

14 comments
October 10, 2012

comments

  1. says

    This was my first year curing pumpkins. I usually sacrifice my pumpkin plants as decoys for the squash bugs. This year I harvested several that were large enough for jack ‘o lanterns. I successfully cured two, but lost 3. Many of our fruits and vegetables are harvested long before it is cool enough to properly store them if you don’t have a root cellar. It’s on my wish list, but i bet I will be wishing a long time. :)

  2. says

    Not about pumpkins:

    Margaret, I’m curious to know how you feel, as time goes by, about addition of the Pin It button. I’ve recently added one, but was rather loathe to. While there are plenty of people who use PInterest with accreditation, most images seem to lose their original credit as they are re-pinned, and, as the creator of the image, this irks me.

  3. Martha Freibott says

    I have planted garlic for the first time. I see that shoots are emerging from the ground. Now what do I do?

  4. says

    I appreciate all the information here. I don’t have that much to save this year (that hasn’t already been canned or frozen), but I am saving these charts for future reference.

  5. says

    Great article!

    We just pulled about 150lbs of sweet potatoes. I’ve previously managed to store them for months (before I knew that was long past their typical storage life, as I’ve now read in multiple places). I wonder why they’ve listed as not keeping well? After they dry, I put them in the dark, unwashed, in a paper bag. That’s worked quite well in the past, but now that I have so many… I’m getting nervous. Before I knew abundance, I didn’t know fear…

    • says

      I bet you do better, Survival Gardener, because you grow in a warmer, longer season. We have trouble up North with getting a consistent crop of fully mature tubers, and I think that has an effect. Plus our winter is hard, meaning we have to find the right spot in our dry, heated homes for these babies. Can be tricky!

  6. says

    I am harvesting Paw Paw from trees planted 15 years ago by a former owner of our house. The tree is beautiful in spring and all year and yields delicious tropical fruit that is pest free.. They taste a bit like banana/mango custard. I highly recommend this hardy native tree.

  7. Victoria Sheridan says

    I do have a root cellar! Our house was built by an Italian immigrant in 1912 and neighbors have told me that during the Depression he used to make wine in the basement. Our root cellar is one of the many splendors of owning an old house and one of the things that really excited us about buying it. I’ve been pretty successful in storing things all year long and only occasionally lose something to spoilage. I’ve found it is a “best practice” to check the root cellar every other day or so just to make sure everyone is ‘happy’. I don’t have a large garden so I buy from our local farmers. At the end of the season they sell off the winter squash for as little as $5.00 a box so I stock up on that and we eat well all winter. I highly recommend a root cellar! Great article Margaret!

    • says

      I am so jealous, Victoria, I could scream. :) And yes, the low-price goodies from the farmers’ market are great value. I love to stock up on whatever I failed with and cook it up or stash it some other way. Nice to see you.

  8. Elizabeth says

    Can you tell me WHERE all these places are with the correct humidity and temperature for storage? I live in Saint Louis, MO. We have 2 refrigerators, a house where the temp is usually 68-70 degrees in the winter and a slightly cooler unfinished basement. Oh- and we have a garage (unheated). These places seem to meet very few of the needs of the vegetables. Thanks.

  9. Pat says

    Thanks for these great tips. One question, how do you clean your root veggies before storing them in a crisper, basement, cellar, etc ? Do you wash and cut carrots? Leave the dirt on them? Wash or not, mine seem to go limp, whether I store in frig or in basement wrapped in newspaper.

    • says

      Hi, Pat. I do not wash and especially don’t cut them. The key is humidity. If it’s not really high, like over 90 percent, they go limp. The fridge is nowhere close to that. I put them in a tightly sealed plastic bag to try to keep them moist in the fridge crisper, but even that has its limitations. Some people store them in damp sand or peat, etc., to keep the moisture in. I have never tried that. Also, starting with a storage variety like ‘Rolanka’ (there are many others) would improve your chances.

  10. says

    Thanks for this wealth of information! I am storing some winter squashes in my basement right now and so far they are lasting. I have a lot of green tomatoes out in my garden right now. Soon we will have a frost so it is helpful to know how long they will last in the house!

leave a reply

Your email address will not be published. Required fields are marked *