Cabbage (Brassica oleracea or variants) is a leafy green or purple biennial plant, grown as an annual vegetable crop for its dense-leaved heads.Cabbage heads generally range from 0.5 to 4 kilograms (1 to 9 lb), and can be green, purple and white.Smooth-leafed firm-headed green cabbages are the most common, with smooth-leafed red and crinkle-leafed savoy cabbages of both colors seen more rarely.They can be pickled, fermented for dishes such as sauerkraut, steamed, stewed, sautéed, braised, or eaten raw.Contaminated cabbage has been linked to cases of food-borne illness in humans.