Greenhouse: How warm can I make my Patio Greenhouse?, 1 by WNYwillieB

WNYwillieB wrote:
Maybe you can place the unit over a basement window and force massive amounts of cellar air up into it, but I agree with ecrane3 ..... it's so small and the plastic so thin, it will be next to impossible to keep warm.

Of course, you have to have a basement with windows to do that (Plus, you should probably have bars on that window). I think if you try to heat that with electricity, it will cost a small fortune, and you would still lose anything tender.

My two-story, 320 sq. ft. greenhouse (not the cold frame) is built right off the house, and uses the basement windows as a forced air heat source for the winter, which works quite well in my situation.

Do you have any alternatives to keeping plants outdoors all winter in your small cold frame? I am in zone 6a and my cold frame, which I built out off a plywood base with old recycled house windows and a poly roof, is attached directly to the garage (southern exposure) but I only get to use is seasonally, like Janet. (see photo)