Cabbage (Brassica oleracea or variants) is a leafy green or purple biennial plant, grown as an annual vegetable crop for its dense-leaved heads. Closely related to other cole crops, such as broccoli, cauliflower, and brussels sprouts, it descends from B. oleracea var. oleracea, a wild field cabbage. Cabbage heads generally range from 0.5 to 4 kilograms (1 to 9 lb), and can be green, purple and white.