Dioscorea bulbifera: Air potato

Family: Dioscoreaceae
Common name: Air potato, Bitter yam, Air yam, Cheeky yam, Potato yam, Aerial yam, Parsnip yam, Karanda

A native of Asia and Africa, these cheeky long Air Potato vines are now baffling plant researchers all over the world with their prolific growth and invasiveness. Air potatoes can grow to a length of 16-18 meters, growing about 20 cm each day, climbing on surrounding vegetation and trees smothering them in the process.

These plants are very pretty with beautiful, green, heart-shaped leaves that are about 15-20 cm long having a unique, uniform venation. The leaf axils or the angle between the leaves and the stem produces small brown potato-like bulbils giving the plant its name air potato.

Though they are called air potatoes, they do not belong to the potato family of Solanaceae, but to the yam family of Dioscoreaceae. These plants also produce tubers in the ground which are like slightly elongated potatoes.

Both the bulbils and tubers are used for food – fried, sautéed, roasted, or boiled; but they are said to have some toxins which are removed through drying or boiling. Unless you are sure that the variant is edible and non-toxic, do not eat the bulbils or tubers of air potato plants.

Air potato plants can reproduce through bulbils that fall to the ground and sprout new plants, and also through tubers that lie dormant in the soil until favorable conditions are available for them to sprout and grow.

For these reasons, many countries are struggling to get rid of these invasive plants that grow quickly covering large areas of land and smothering native species. In Florida, there is a special task force formed to explore the biological control of air potatoes using the air potato beetles that only feed on these specific plants.

Air potato plants mostly grow in warm, tropical weather, though they are capable of growing in temperate climates, where the vines die back and the tubers lie dormant in the soil during winters.

Traditionally these plants have been used in the treatment of diarrhea, dysentery, cuts, wounds, skin infections, ulcers, cough, diabetes, and conjunctivitis in folk medicine. One of the compounds in this plant is used to produce steroids in the pharmaceutical industry.

Propagation is through tubers or bulbils, both very effective in creating new plants invading new areas of land.