Cauliflower is one of several vegetables in the species Brassica oleracea in the genus Brassica, which is in the Brassicaceae family. It is an annual plant that reproduces by seed. Typically, only the head is eaten – the edible white flesh sometimes called “curd”.

Cabbage is a leafy green, red, or white biennial plant grown as an annual vegetable crop for its dense-leaved heads. It is descended from the wild cabbage, and belongs to the “cole crops” or brassicas, meaning it is closely related to broccoli and cauliflower; Brussels sprouts; and Savoy cabbage.

Romaine or cos lettuce is a variety of lettuce that grows in a tall head of sturdy dark green leaves with firm ribs down their centers. Unlike most lettuces, it is tolerant of heat. In North America, romaine is sold as whole heads or as “hearts” that have had the outer leaves removed and are often packaged together.