8 Frost Resistant Vegetables

http://garden.lovetoknow.com/wiki/8_Frost_Resistant_Vegetables

Broccoli can tolerate temperatures from 26 to 31 degrees.

Cabbage likes cool temperatures as low as 26 degrees depending on the variety.

Kale can withstand temperatures as low as 10 degrees.

Peas can tolerate light frosts with temperatures from 31 to 33 degrees.

Spinach can tolerate temperatures as low as 20 degrees.

The top leaves of turnip will die back if temperatures drop below 10 degrees or so, but the root itself will still be good to eat.

http://www.examiner.com/article/a-list-of-frost-hardy-and-cold-hardy-plants-for-your-garden

A list of frost-hardy and cold-hardy plants for your garden

This post was edited by JCTsai on Sun, Nov 9, 14 at 19:39

Lettuce and chard should be covered. Broccoli can handle 25 but only if it is watered and doesn't get a dry wind. In my region of central MN leeks and spinach usually overwinter under snow. Pea plants can get very cold but pea flowers die under 30. There is some difference between a plant becoming unusable and actually dying.

All of them can take 28. Define "which temperature they can take". Take what? Without dying to the ground? or so that you can not harvest them until the next thaw? My swiss chard took 23 about a week ago, and should be good to 18F at least (without dying). Spinach will take 14F or less. My lettuce overwinters in hoop houses, so it, too (at least the hardy varieties such as romaine) takes low temps, in the single digits. And surely spinach is hardier than lettuce.

None of them would even bat an eye at 28 degrees. Once you get into the mid-20s, lettuce will show damage, followed by escarole. Broccoli and swiss chard are hardy to the high teens (broccoli leaves can handle the low teens, but heads are not as hardy). Spinach is hardy to single digits, and the edible part of leeks is hardy to 0 F because it is near or below the soil line.

I just had some chickpea seedlings tolerate a 14-degree freeze inside a coldframe completely unfazed. (it was 14 degrees inside the cold frame and 2 degrees outside).

Agree with the above posters. I have had broccoli tolerate low 20's on many occasions. The duration of the lows is the key determinant on survival. We seldom get into the low 20's for more than a few hours. However, If we get temperatures that remain in the high teens to low 20's for a couple of days I begin to lose plants.

Thanks all! This is great stuff.

What about leeks? I tried a fall crop for overwintering this year and I'm not quite sure of the timing of planting or how much protection (and when) they need it.

Here are the varieties and days to harvest (planted out August 24):

King Richard (75 days)
Tandora (100 days - overwintering variety)
Bandit (120 days - very winter hardy)

The words in parentheses are from the seed packets.

What do you think about covering these? Is the cover to keep them warm or is it for protection from snow?

Snow is good -- it is "cover" essentially.
In northern Va I would think all your leeks would be fine with no cover (I've had leeks in Maryland D.C. suburbs do fine with no cover.)
Of course, that depends on how many polar vorteces we have this winter.

Heavy mulching with leaves, straw or hay should do the trick if it starts getting down to single digits.

Leeks are probably the most hardy of all.

My leeks did fine last winter when the temps dropped to about 8F and never got above 20F for about 5 days.
Some of them got a bit mushy, but most were in salable shape.
-Mark