Growing vegetables outside in the winter isn’t as absurd as it sounds. There are several root vegetables that can be left in the winter for harvest and actually get better with the cold winter. Two of these that we like are salsify (oyster root) and parsnips. Another is Jerusalem artichokes. Salsify tastes and smells a little like cooked oysters when it is steamed or fried in oil. Parsnips smell and taste a lot like carrots. Jerusalem artichokes are delicious sauteed and taste a lot like an artichoke heart.
Salsify and parsnips are planted as seed in the spring but Jerusalem artichokes are sunflower-like plants that grow from roots collected the previous year. Actually, if you start a patch of Jerusalem artichokes, they will just come back each year unless you are very thorough at digging up all of the bits and pieces of the previous year’s roots. The photo below was taken in November 2012 and shows some of these root crops that were dug from our garden for Thanksgiving dinner.
The root crops mentioned above don’t really “grow” much in the winter but there are some that do. For instance, corn salad is a green that will continue to grow through the winter in areas that are relatively mild. But if you really want to cash in on winter greens a cold frame is the way to go.
It’s great to get fresh lettuce from your own garden in the dead of winter. A cold frame can provide you with fresh lettuce. It’s possible to get lettuce all winter long if you plant in the fall and stagger your plantings so some lettuce is always maturing.
So far, the best crop for our cold frame has been the butter crunch lettuce variety. It seems to thrive in the short days and cool temperatures and does not succumb to the very cold nights when the temperature in the cold frame can drop below freezing.
The cold frame shown below is built from outdoor plywood. The door frames are made from strips of plywood and the the transparent door material is plastic that was scavenged from a big plastic bag that a mattress was shipped in. The doors face south and the sun really warms things up in there. It is even possible to germinate lettuce and spinach during the winter.
I’ve seen other people build cold frames that are made from glass doors sitting on some bricks or cinder blocks and those work just fine. Of course you can buy a kit too but building a cold frame from scavenged materials is much cheaper.
Fresh lettuce in winter. At TFF we have a small home-built cold frame that we use to raise lettuce and spinach in the winter. These photos were taken in the middle of February 2013.