I purchased a cold frame from mail order a few years back. It was made in
Germany, I believe, of a corregated plastic material. One nice accessory they
sold
was a thermal controlled lifter, that would open the top door of the frame
automatically, depending on the outside temperature. I have used it for
years, and it
works for me. There are probably many variations of this product, if you just
scan the catalogs and internet.

Sherwin Dubren

Gary and Karen Manning wrote:

I am considering building a cold frame. My question is: how do I keep the
plants from cooking on worm sunny days? I don't want to stay home because
the sun may come out.

Thanks

Gary