Lesser Yam, Potato Yam, Chinese Yam, Wild Yam
Dioscorea esculenta

Family: Dioscoreaceae

What it is like

Lesser Yam or Dioscorea esculenta is a perennial, climbing plant with a tuberous rootstock. It has spines and it can climb up to about 2.4 m high and spread up to 1.8 m across. The leaves are often heart-shaped It is often cultivated as root crop in tropical areas in East Asia. Though some varieties can be poisonous, most are edible. The tuber has a yellow or white flesh. It is cooked and used as vegetable. It has a sweet and pleasant flavour similar to that of sweet potato or chestnuts.

Dioscorea esculenta is an evergreen Perennial Climber growing to 3 m (9ft) by 0.5 m (1ft 8in) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 9. The flowers are pollinated by Wind, Insects. Suitable for: light (sandy) and medium (loamy) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.

Height (m): 3

Where it is found

Not known

E. Asia - India, Nepal, Bangladesh, Myanmar, Thailand, Vietnam, Malaysia, Indonesia, Philippines, New Guinea.

Conservation Status: This taxon has not yet been assessed.

Countries/locations it is found in

Africa, Asia, Australia, Bangladesh, Brazil, Burma, Cambodia, Central Africa, Central America, China, Comoros, Congo, Cook Islands, Côte d'Ivoire, East Africa, East Timor, Fiji, New Caledonia, Ghana, Guiana, Guyana, Hawaii, India, Indochina, Indonesia, Ivory Coast, Japan, Laos, Madagascar, Malaysia, Martinique, Myanmar, Nauru, New Caledonia, Nigeria, Northeastern India, Pacific, Papua New Guinea, Philippines, SE Asia, Solomon Islands, South America, Sri Lanka, Taiwan, Thailand, Timor-Leste, Togo, Tonga, USA, Vanuatu, Vietnam, West Africa, West Indies,

How it is used

Food

Rating: 4

Root - cooked and used as a vegetable. Sweet and pleasant, with a flavour somewhat like sweet potato or chestnuts. The tubers are oval, up to 20cm long and 6 - 8cm in diameter. Each plant can produce 5 - 20 tubers. The flesh is yellow or white and the average tuber weight may be 250 - 1,000g, though larger ones can weight 3,000g.

Root: includes bulbs, corms, tubers, rhizomes etc.

Medicine

Rating: 0

Other

Rating: 0

Food Forest: Plants for Edible Forest Gardens and Food Forests.

How it is grown

A plant of the drier to wet tropical lowlands, where it is found at elevations up to 900 metres. It grows best in areas where annual daytime temperatures are within the range 28 - 32°c, but can tolerate 17 - 45°c. It can be killed by temperatures of 9°c or lower. It prefers a mean annual rainfall in the range 800 - 2,000mm, but tolerates 600 - 8,000mm. Plants like a well-defined dry season of 2 - 5 months. This species will grow in drier climates than other yams, so long as the rainfall is evenly distributed through the year. Succeeds in full sun and also in light shade. For best yields, this species requires a deep, well-drained, sandy loam that is not liable to water-logging. This species will succeed in poor gravelly soils, especially if enriched with organic matter. Prefers a pH in the range 5.5 - 6.5, tolerating 4.5 - 8.5. Daylengths of more than 12 hours are preferred during the early growing season since this encourages vegetative growth; daylengths of less than 12 hours towards the end of the growing season will encourage tuber formation and development. Crops take 7 - 10 months to mature, yields of 7 - 20 tonnes per hectare have been achieved. There are some named varieties. Two main forms of this plant are sometimes recognised: Var fasciculata (Roxb.)Prain. & Burk. Arose in cultivation and has no spines. Var spinosa (Roxb.)Prain. & Burk. Is believed by many botanists to be the wild form. It has thorny roots protecting the crown of the rootstock. This is a variable characteristic, however. The plant rarely produces flowers. A dioecious species, both male and female plants need to be grown if seed is required.

Propagating it: Seed - not normally used to propagate this species. Cuttings of tubers. Pieces of tuber, each weighing around 50 - 80g with dormant buds, are planted in situ 4 - 8cm deep with the stem pointing downwards. The cut tuber is often first left in the sun for several hours to promote wound healing and reduce the risk of fungal infection.

Best place to grow:

Habit: Perennial Climber

Hardiness: 8-12

Growth: Fast

Soil: Light (sandy), medium

Shade: Semi-shade, no shade

Moisture: Moist

Things to keep in mind

Edible species of Dioscorea have opposite leaves whilst poisonous species have alternate leaves.(Parts of plant are poisonous if ingested)

Its other names

Local names

Ama-yama-imo, Apali, Birch-rind yam, Buga, Couche-couche douce, Cu tu gai, Diba, Gan shu, Gembili, Goa potato, Harau, Hisu, Huwi butul, Huwi jahe, Huwi kamayung, Huwi landak, Kangar, Kawai, Kembili, Kemili, Kizahangu Kodi, Manalu, Man-chuak, Musilam valli kilangu, Pana, Sasniali, Sathni, Silakadom, Sinnavalli-kelangut, Siruvalli kilangu, Siu-chue-shue, Su nialu, Sudo, Suthni, Taitu, Taitukava, Tippa tiga, Tivvitiga, Tonga, Tu gai, Tugi, Tungo, Ubi-arumanis, Ubitorak, Ufi Lei, 'Uhilei, Uwhikaho, Wale, Ware, Yava-ala,

Synonyms

Dioscorea aculeata L. Dioscorea fasciculata Roxb. Dioscorea papillaris Blanco Dioscorea papuana Warb