Tropical Ingredients

Winged Bean

Psophocarpus tetragonolobus

Almost the entire plant is edible.

5 min read·Updated September 24, 2026
Growing regions: South and Southeast Asia
Other names: Goa bean, Four-angled bean, Asparagus pea, Princess bean, Manila bean (English); Dambala / Dara dambala (Sinhala: දඹල); Sirahu avarai (Tamil); Kacang botol (Malay/Indonesian); Sigarilyas (Tagalog); Thua phuu (Thai)
Family Fabaceae Best for Stir-fries, soups, curries, salads

Description

The winged bean is a climbing legume best known for its pods, which are square in cross-section and carry four thin, frilled "wings" running their length — the feature that gives the plant its name. It is a twining perennial herb in the pea and bean family, Fabaceae, grown in the humid tropics and, in most gardens, treated as an annual.

What makes the winged bean remarkable is that almost the entire plant is edible. The tender young pods are eaten as a green vegetable, the leaves cooked like spinach, the flowers added to salads, the tuberous roots boiled or roasted like a root vegetable, and the mature seeds used much like soya beans. This completeness has earned it the nickname "one-species supermarket," and its protein-rich seed the title "soybean of the tropics."

Not every part is eaten the same way, and not all of it is eaten raw. The young pods and flowers can be eaten raw, but the mature dried seeds contain anti-nutritional factors and a hard seed coat, so they must be soaked and well cooked before eating.

Origin & History

Winged bean grows throughout South and Southeast Asia, from India and Sri Lanka across to Papua New Guinea, the Philippines and Indonesia, where it has been cultivated for a very long time. Its precise wild origin is debated — Papua New Guinea and Southeast Asia are both suggested — but it is firmly established as a traditional crop across the region.

Interest in the plant surged in the late 1970s, when a widely circulated National Academy of Sciences booklet introduced it to a wider world as a high-protein crop for the tropics. A second international conference was held in Sri Lanka in 1981, reflecting the role the country has played in its cultivation and study. Sri Lankans have long called it dambala and grow it year-round, eating the young pods raw or cooked.

Its roots fix nitrogen, so it grows on relatively poor soil as a crop or a cover crop.

Uses

Culinary

  • Young pods: Sliced and stir-fried, boiled or steamed as a green vegetable; also eaten raw when very tender
  • Immature seeds: Cooked in soups and curries, with a sweet, pea-like flavour
  • Mature dried seeds: The protein- and oil-rich seed, boiled, roasted or fermented after soaking and thorough cooking
  • Leaves: Cooked like spinach or another leaf vegetable
  • Flowers: Used raw in salads and to add colour to dishes
  • Tubers: Boiled, steamed, fried or roasted as a starchy root vegetable with a nutty, slightly sweet character

Other Uses

The seed can be pressed for edible oil or ground into flour, and in Southeast Asia is turned into tempeh, tofu and a soya-like milk. The plant is also used as animal feed and, thanks to its nitrogen-fixing roots, as a cover crop.

Nutritional Benefits

Winged bean is best known as a protein crop. The mature dried seeds contain roughly 30–37% protein with a fat content around 15–18%, a profile frequently compared with soya beans, along with useful amounts of carbohydrate, fibre and minerals. The tubers are starchy and carry more protein than a typical root vegetable, while the leaves and flowers contribute smaller but worthwhile amounts.

The same seed that is so nutritious also demands respect in the kitchen: it holds anti-nutritional factors that soaking and thorough cooking reduce. These are described qualitatively here — the plant's value is as a versatile whole food, not as a measured supplement or a medicine.

How to Prepare

  1. Choose the right stage: Pick firm, tender young pods for quick cooking; select mature pods for their dried seeds; harvest tubers after the plant matures.
  2. Young pods: Trim the ends and any strings, slice, then stir-fry, boil or steam briefly. Very fresh pods can be eaten raw.
  3. Leaves: Wash and cook as you would spinach, briefly and with seasoning.
  4. Flowers: Rinse and use raw in salads.
  5. Tubers: Scrub, peel if desired, then boil, steam, fry or roast until tender.
  6. Mature dried seeds — cook thoroughly:
    • Soak: Presoak the seeds well; the hard, tightly adhering seed coat slows water uptake and cooking
    • Cook long: Boil until fully tender. Dried seeds need much longer cooking than most pulses — several hours is not unusual — so pressure-cooking is a practical shortcut
    • Never eat mature dried seeds raw or undercooked
Tips: The young parts give the plant its fresh, green appeal; the mature seeds give it its substance, but only when properly cooked.

Recipes

As Jungle Kitchen develops recipes featuring winged bean, those will be linked here.

Suggested applications: stir-fried winged bean pods with garlic, winged bean salad with raw flowers, simmered young pods in coconut curry, roasted winged bean tubers.

Varieties

Winged bean is usually treated as a single species rather than through formally named varieties. Plants differ in pod colour — green and purple types both occur, with or without flecks — in seed-coat colour from cream through brown to black, and in whether they are grown mainly for pods or for tubers. Choose by freshness and what you intend to eat, rather than chasing a specific cultivar name.

Fun Facts

  • The pods are literally four-cornered, each edge fringed with a thin wing that gives the plant its name.
  • It is sometimes called the "one-species supermarket" because nearly every part of the plant can be eaten.
  • The mature seed's protein and oil profile is close enough to soya beans to earn it the label "soybean of the tropics."
  • A single pod can hold a dozen or more seeds, and the plant carries pods, leaves, flowers and underground tubers all at once.