Glycine max Half oz packet sows 10 ft; 1 lb, 320 ft. Avg 80 seeds/oz. Used in China more than 2,200 years ago, then introduced into Japan. The Japanese call them edamame (eh-dah-mah-may), meaning ‘beans on branches,’ and boil and salt them like beer nuts. Edamame are rich in vitamins A, C and E, calcium, phosphorus, protein and dietary fiber. Encouraged by its recent popularity surge, breeders are selecting for larger pods with sweeter beans.
Culture: Edamame are day-length sensitive. Sow around the same time as sweet corn and harvest when most of the pods have expanded but are still green without yellowing. For best flavor harvest in the evening.
Steam or boil the pods for 4–5 minutes, chill quickly for easy shelling. Refrigerate the leftover beans immediately. Fresh-market growers often cut off plants near the base, remove the leaves and bunch into 1 lb units, rather than pick each pod individually.
Good companions: Seedsman Tom Vigue plants edamame in the same furrow as his sweet corn. He thins each to one plant per row foot and suffers little yield loss from either crop: the soybeans are a gift. He sows a living mulch of forage radish that takes off after both main crops are dead. He follows the next year with potatoes which benefit in rotation from all three of these crops.
Saving seed: Soybean seed is easy to save; expect about 1 lb per 10 row feet.
Pests: Young plants 2nd only to brassica seedlings as woodchucks’ preferred gourmet treat. Japanese beetles also love them but can be controlled by assiduous hand-picking.