Hello all. Mark here, been a while. Had a cactus party this summer and was left with more then just prickly pear cactus, as my sun room is full up with succulents i decided to make a cold frame out of some left over building material i had been hording since last fall. Here is photos, it contains pricklys, agave, mamalaria, notocactus, ferrocactus, graptoveria, ETC . I did not insulate the bottom or sides and there is a 1 1/2 inch gap all the way down the front of the window. the window swings on three hinges and rests on a board for airing out. THinking about cutting ridigid foam for fit bottom and front gap but worried i will then cook cacti on hot day. Will update later this winter or spring let know survival rates.