I don't know if anyone knows what a cold frame is but I wanted one for a long time. Maybe you call it by a different name but basically a cold frame is somewhere to propagate seeds outside under glass. Usually it sits on the ground and is a few inches tall buy a couple feet wide.
I looked at plenty and almost bought one but instead remembered we had a sheet of perspex that we hadn't used from another project. I got Seb to design and make one for a fraction of the oct to buy. The beauty about Seb's cold frame is that it's totally okay to dismantle when we are done with it. Okay, so the construction is basic, just bricks and the top to shield the plants, the plants don't care that it's crude.