Bitter melon, a vining herb that can reach 6 feet or more, grows in tropical areas, including parts of Africa, Asia, the Caribbean, South America, and the Pacific Islands. The species includes two basic forms: a wild type with very small (about 1½-inch-long) inedible fruits and a cultivated form with much larger fruits reminiscent of a ribbed cucumber, covered with warts or bumps.
When ripe, the fruit turns yellow-orange and splits open to reveal seeds covered with red pulp. Despite its extremely bitter flavor, the fruit is eaten as a vegetable — raw, pickled, or cooked — in its native regions, and it is commonly sold in Asian markets in North America.
Bitter melon has a long history of use in Asian traditional medicine, as well.
The fruit of the cultivated bitter melon (left) is edible and much larger — 8 to 12 inches or more in length — than the fruit of the wild type (right) — 1 to 2 inches long — which is not eaten and is used for its medicinal value.
Common Names: Bitter Melon, Bitter Gourd
Description: Annual vine, 6 to 10 feet long; alternate, deeply lobed leaves; yellow flowers; oblong, warty fruit ripens to yellow-orange; seeds of ripe fruit covered in bright red pulp
Flowering: Early to midsummer
Parts Used: Fruit, leaves, shoots, and roots
Range/Habitat: Native to Africa, Asia, the Caribbean, South America, and the Pacific Islands
Usually, bitter melon fruit is harvested and eaten when green; as it ripens, it loses its distinctive bitterness. The fruit is often cooked in soups and with meat, stuffed, or cut into pieces and boiled. In India, the peeled fruit is soaked in salt water before cooking to reduce some of the bitterness. Thai cooks fry the fruit with eggs. Asian cooks also stir-fry the shoots and young leaves, which are a rich source of vitamins A and C, as well as calcium. The people of the remote Pacific Islands of Micronesia even cook and eat the plant’s roots.
This plant is used as a healing herb wherever it grows. In Thailand it is used as a tonic and to treat skin diseases. Ayurvedic medicine recommends the fruit, leaves, and roots for the treatment of type 2 diabetes. Laboratory studies with animals have shown that both a fruit extract as well as the fried fruits improved glucose tolerance, one of the goals of treating type 2 diabetes. A small study with humans showed an increase in glucose tolerance in 73 percent of patients who consumed the fruit juice.
In India, the fruit of the wild plant is used to lower fevers, while the cultivated fruit is eaten to treat arthritis, gout, and liver and spleen conditions. In Belize, where this is one of the most important medicinal plants, people boil the leaves and vines of the wild plant to make a beverage that they drink to treat parasites, amoebas, and constipation. The plant is also added to bathwater to treat skin infections, tick and chigger bites, sores, and wounds.
Caution: This herb should not be used by pregnant women, nursing mothers, or young children.
How to grow it
Bitter melon is easy to grow in fertile, well-drained soil and full sun. Start the seed indoors 4 to 6 weeks before your last frost date, then transplant the seedlings to your garden after all danger of frost has passed. Provide support for the climbing vines, and water them regularly. Fruiting should begin about 60 days after transplanting; harvest when the fruit are light green. Propagate by seed.