Many hardy root vegetables don’t need to be dug up and stored for the winter. These frost tolerant veggies can be stored in the ground down to 10°F
I can be a bit of a lazy gardener — I love working in the garden but if there’s something I can save time on then I’m all over it. One thing that I’m a big fan of is not having to dig and store vegetables over winter. Why do it, when a lot of them can be left in the ground?
Though temperatures below 25 °F (-2.2 °C) can wipe out root veggies, anything up to that point is safe for beets, parsnips, kohlrabi, turnips, radishes and carrots. The foliage will die back for the most part but the tasty bit in the ground will store well enough. Put a bit of mulch over the top and they’re protected at even cooler temps.
It all comes down to frost tolerance. My garden is in coastal Britain’s zone 9 which has very mild winters. I don’t worry as much about my hardier veg because it rarely freezes here. Even so, some edibles need a good 6-12″ mulch of straw or leaves to keep them protected from the frost.
If you’re in a colder zone, you shouldn’t chance being a lazy gardener. Make sure to store root veggies in cool sheds and garages where hard freezes can’t touch them. This is especially true for if your soil is wet. I once saw a friend’s 20 foot row of carrots go to waste because of intense cold. It froze the roots solid and they went to mush when the temperatures warmed.
Harvesting & Storing
Each edible has a different tolerance to the cold so keep that in mind as you plan your harvest. Whereas I feel relatively safe leaving my root veggies in the ground, others in colder temperatures know too well what can happen.
If you expect temperatures down to 25 °F (-2.2 °C) then dig and pack them away. If not, leave them in the ground until you need them. They may be nibbled by beasties over winter but organic gardeners are tough and we can overlook a few holes.
Beets — Will stand their ground at sustained temperatures of 30 °F (-1 °C). If left in the garden all winter the roots will produce very early spring greens. Make sure to harvest them before they regrow these leaves or the flesh will be woody.
Carrots — Known to withstand temperatures of down to 20 °F (-6 °C) if properly mulched. They also store well in boxes of damp sand kept in a cool, dark place.
Cereriac — cannot withstand a hard freeze but will tolerate light frosts, especially with protective mulch. Like carrots, they can be stored in boxes of damp sand.
Kohlrabi — this above the ground ‘root’ vegetable gets sweeter after a frost. It doesn’t like hard freezes though so protect them with straw until you need them.
New Zealand Yam (Oca) — This south american tuber sleeps very happily through light frosts. It can’t stand a hard freeze though so dig them up and store as you would potatoes two weeks after the foliage has died back. They don’t begin forming tubers until autumn so this is one of the last veggies you need to store if need be.
Parsnips — the cold makes the parsnips even sweeter! They’re hardier than carrots, though in the same family, and will survive until spring if left in the ground. Temperatures of down to 0 °F (-18 °C) won’t phase them if mulched.
Potatoes — ever had a volunteer potato plant before? Then you know they can survive under the ground during a mild winter. Dig up as necessary in mild winters but it may be better to dig and store them in a cool place. Slugs can become a problem in the ground. Mice and rodents can be an issue in storage so keep an eye on them.
Radishes — there’s a world of radish varieties out there including some rather large winter types. These take longer to grow and will not become woody if left a little longer in the soil. I can recommend Black Spanish Radishes for in-situ storers.
Turnips — Very hardy. Some varieties can withstand down to 10 °F (-12 °C) if properly mulched. Interestingly, the spiciness of summer turnips changes to sweetness with the cold.
Swedes — As hardy as the turnips and a good winter staple.