A short-lived herbaceous plant with upright stems usually growing up to 1.7 m tall. Its stems are finely ribbed and sparsely hairy. Its alternately arranged leaves are once-compound with three leaflets (2-10 cm long)its pea-shaped flowers are arranged in elongated clusters (8-35 cm long) at the top of the plant. These flowers (7-8.5 mm long) are yellow with reddish-purple veins and a dark patch near base. Its small pods (18-35 mm long and 4-6 mm wide) turn blackish as they mature.