Plant · P-244

Winged Bean

Psophocarpus tetragonolobus

Winged bean may be the most complete food package of any single plant here: the pods cook like French beans, the mature seed is rich in oil and protein, the tuberous roots eat like a potato with roughly double a potato's protein, the leaves cook like spinach, and even the flowers are edible, tasting faintly of mushrooms when sauteed. It is also the strongest nitrogen fixer in this group, producing more root nodules per plant than any other legume tested. The catch is day length: an ordinary variety only flowers once days shorten to around twelve hours, so a spring-sown plant spends the whole summer as vine and gets just a short, weather-exposed pod harvest before frost - a day-neutral variety turns that gamble into a summer-long yield instead. It climbs on a trellis rather than running, and needs steady moisture on ground that drains.