DH built me a cold frame this year. He 'improved' on it and it is now tall enough that I can walk into it to work. It looks more like a plexiglass lean to. The plexiglass (The sheets you can get from a greenhouse supplier)is on the south side and the north side is wood. I plan to insulate the north side for the winter. It gets warm enough in there during the day, to hot in fact, during the summer but now since the weather is cooling so much, I want to plant cool weather crops in it, lettuce, radishes, spinach, chard, to start. I recommend you go to the library and check out some of the books by Eliot Coleman. I have all of his but especially like his last one, The Winter Harvest Handbook. He lives in Maine and if he can grow in winter I don't see why I can't. Good luck! Marg

Yup, Eliot Coleman's books will be very helpful to you. Just keep in mind though, that we live so far up in the tundra that midwinter in Maine is like November in SK :o)

Definitely cover it (glass is better than plastic) as long as you vent on sunny days. The added warmth will make a big difference. If you want to, get a min/max thermometer from Canadian Tire, put it into a small, hollow, white styrofoam box and place it inside your little greenhouse to see how warm it is at night and how much you need to vent during the day...You might also want to use a soil thermometer to see how cold it can get before the soil freezes. It will freeze before in-ground beds.

I have a cold frame, so maybe i'll give it a shot.