Perennial climbing or trailing herb, growing from a woody rootstock. Leaves imparipinnate with 2-4 pairs of leaflets and a terminal leaflet. Leaflets ovate to elliptic-oblong, up to 6.5 × 4 cm, mostly hairless above, pubescent below. Flowers axillary, solitary or 2 together, resupinate, large and showy, bright blue with a with centre, sometimes completely white. Standard up to 5 × 4 cm. Pod linear-oblong, 6-13 cm long, flattened, mucronate at the apex, hairless or finely pubescent.