Annual herbs, 50-200 cm tall. Stem climbing, much branched, somewhat hairy, winged. Leaves with branched tendril at apex; rachis winged; stipules semisagittate; leaflets 1-paired, ovate-oblong or elliptic, 20-60 × 7-30 mm, with pinnate veins, rarely subparallel veins, margin entire. Raceme longer than leaf, 1-3(or 4)-flowered. Calyx campanulate, equally toothed and longer than tube. Corolla usually purple, or other colors, 20-30 mm. Ovary linear; style twisted. Legume brown-yellow, linear, 5-7 cm, pubescent. Seeds smooth. Fl. and fr. Jun-Sep.
"A wing-stemmed annual with fragrant fls 2–4 cm, occasionally escapes, but apparently does not persist."
Annual, stem pubescent, winged. Leaf paripinnately compound, leaflets 2, 2-6 cm long, 7-30 mm broad, elliptical or ovate-oblong. Stipules 1.5-2.5 cm long, semisagittate. Inflorescence 1-3-flowered. Calyx 10-11 mm long, teeth almost equalling the tube. Corolla white, pink, purple, violet or blue in various cultivated forms, 2-3.5 cm long. Fruit 5-7 cm long, 10-12 mm broad, pubescent, 8-seeded.