Fava bean annual herb, 30-100 cm tall, main root short and thick, many fibrous roots, rhizomes pink, dense, leaflets usually 1-3 pairs, alternate, upper leaflets can be up to 4-5 pairs, less basal, leaflets elliptic, oblong or obovate, sparsely rounded, apex rounded, mucronate, base cuneate, entire, glabrous on both sides.

Racemes axillary, pedicels nearly absent; calyx campanulate, calyx teeth lanceolate, lower calyx teeth longer; with 2-4 flowers in clusters inserted in the leaf axils, corolla white, with purple veins and black halo, pteropetalous petals shorter than flagellar petals, longer than keel petals; style densely whitish pilose, with a bundle of bearded hairs on apical distal surface of axis.

Pods plump, 5-10 cm long, 2-3 cm wide; epidermis green tomentose, with white spongy, transverse membranes, epidermis turning black at maturity. Seeds 2-4(6), oblong, suboblong, concave in the middle;

seed leathery, greenish, gray-green to tan, sparsely purple or black; hilum linear, black, located at one end of the seed. Fl. April-May, fr. May-June.

Extension:

Growing environment

Fava beans are born in the warm wetlands of 63 ° north latitude, tolerate -4 ° C low temperature, but fear of the heat, the temperature requirements with the changes in the reproductive period, the appropriate temperature for seed germination of 16-25 ° C, the lowest temperature of 3-4 ° C, the highest temperature of 30-35 ° C;

In the nutrient In the nutrient growth period requires a lower temperature, the minimum temperature of 14-16 ℃, flowering and fruiting period requires 16-22 ℃, such as -4 ℃ below the low temperature, its aboveground will suffer from frost damage.

Cultivated throughout China, south of the Yangtze River for the victory. Native to the Mediterranean coast of Europe, southwest Asia to North Africa.