Last week, we began working on a project to bring fresh produce to tables in Oberlin throughout the winter. If you’ve never seen a cold frame before, it’s basically a low wooden box with a clear lid that works like a greenhouse for hardier crops (root veggies, greens). Cold frames can extend the growing season into the late fall for plants that fear the frost, through the winter for greens that do well in cold weather, and provide warm, indoor conditions for seedlings in the early spring.
For a college, where the majority of the population leaves town during the peak growing season, winter gardens are a viable option for giving students a satisfying seed-to-table growing experience while localizing our food production during a time of year when much of our produce comes from the farthest-flung farms.
Eliot Coleman is a farmer and author famous for his innovative farming practices at his farm in Harborside, Maine. In spite of the harsh climate, Coleman and his wife Barbara Damrosch maintain gardens all year round in unheated and minimally heated greenhouses, hoop houses and cold frames. Following the blueprints in his book Four-Season Harvest, RCT and OGROW wrote a Green Edge Fund grant proposal to buy materials for five 4’x8′ cold frames and their polycarbonate lids, or “lights.”
The wooden frames themselves need to be aligned east-west, with lights angled south to capture the most winter sun. The beds in the garden are currently aligned north-south, which is neither optimal in terms of maximum sun exposure, nor in terms of drainage, as the western end of the garden has the lowest gradient. Aligning the beds east-west would allow more rainwater to drain down the compressed walkways between beds rather than pooling up beside row after mounded row.
For now, we positioned the frames aligned east-west, directly crossing paths with the current beds, now mainly hosting some collards and old tomato plants.
We have so far transplanted a few frames worth of spinach and kale from the outdoor beds into the frames.