Any one of a number of annual crucifer species of Asiatic origin belonging to the plant order Capparales. Mustards eaten as greens are Brassica juncea, B. juncea var. crispifolia, and B. hirta. Table mustard and oils are obtained from B. nigra. Cultural practices are similar to those used for spinach. Southern Giant Curled and Ostrich Plume are popular varieties for greens. Long days and high temperatures favor undesirable seed-stalk development. Harvesting is usually 1½–2 months after planting. Important production centers for mustard greens are in the South, where the crop is popular. Montana and the West Coast states are important sources of mustard seed.