Living in a corner of southeastern Wyoming, we are in zones 4 and 5 However, you can pick fresh vegetables in winter, even after sub-zero. Here's how it goes.
They are single layer without additional heat greenhouses. Crops include in bok choy, kohlrabi, lettuce and chard - all for their resistance to cold temperatures is known, but not resistant vegetables. The plants are cut in half is done in raised beds of 55-liter steel drums, sotheir position about 1.5 meters above grade level.
Self Pest Control
The raised beds can easily absorb heat, but also to heat more easily to their environment. In addition, there are other sources of heat other than the sun, and no heat storage mechanism different from that of the surrounding terrain.
The steel barrels raised beds are covered with 6 mil poly cover. There is a tendency on the battery and is absorbed by plants through the PVC tires, which are held in various locations arc.
Even after 36 hourscontinuous freezing temperatures that the fund unless 14 F, we are still able to collect our vegetable crops with little damage to their quality. To put things in perspective, less than 14 F is 45 degrees below the point at which water freezes. Not exactly the kind of time that the most associated with increased production of vegetables, but a good test of winter vegetables and its resistance with a double layer of protection.
After our period of intense cold, I waited a day or two, sothe temperature in the greenhouse to get much above freezing, before I checked on the "guinea pigs" horticultural crops. Beat all the plants looked like a small, but had not been eliminated cold, or otherwise destroyed by the bitter cold. They all looked as if they were on the mend. It 'was really an amazing spectacle.
I picked up the bok choy and found the plan as a raised bed frozen too hard. The plants were fine, but the ground was hard as a rock. I had tocut it off just above the ground to collect them. A half dozen beets were harvested. A train heavy peaks are released from the grip of ice well composted soil. The taproot has long been associated with the swollen part of the turnip root encrusted with frozen soil.
In the midst of the harsh winter, we were harvesting vegetables planted in the fall. Just think what it covers, with the additional set, cold frames and more hardy winter vegetables are done.
If youthought that gardening is only for the summer, my experience proves otherwise.
Winter gardening - to below freezing