The plant genus Cucurbit consists of various squashes. The winter varieties have thick, inedible skins, and so store well. They are also very sweet. Summer squash, on the other hand, have a very thin skin, which can be eaten. All species are sensitive to frost. They usually have large, yellow or white flowers which can be eaten. Both male and female can be found on a plant. We commonly grow varieties from 3 species - pepo, maxima, and moschata. Varieties cross within the species but not across species.