Gastrodia elata

A genus of 20 saprophytic species of orchids, found in E Asia to New Zealand. They are extremely difficult to cultivate because of their lack of green parts and complete dependence on a fungus for food. Gastrodia elata was first described in traditional Chinese medicine c.CE470. The literal translation of the Chinese name is "heavenly hemp". Due to its increasing rarity in the wild, techniques for cultivating this saprophytic orchid have now been devised in China.

Perennial, leafless saprophyte, with an angular, horizontal, tuber-like rhizome, 10-15cm (4-6in) ong and 5-6cm (2-2½in) wide, and brown stem clad in scale-like sheaths. Small, pale green-brown flowers appear in summer.

Common Name:	Gastrodia elata
Botanical Name:	Gastrodia elata
Genus:	Gastrodia
Family:	Orchidaceae
Cultivation:	Damp rich soil in shade, in association with a fungal partner.
Propagation:	By seed sown when ripe in the natural habitat near existing colonies, or on to a bed of Quercus wood, inoculated with the fungus Armillariella mellea; by division of rhizomes during dormancy.
Harvest:	Rhizomes are lifted in autumn and dried for use in decoctions.
Native Location:	China, Japan, Korea, Tibet, Siberia.
Height:	60cm-1m (2-3ft)
Width:	30cm (12in)
Hardiness:	Z2-8
Parts Used:	Rhizomes (tian ma)
Properties:	A sweet, acrid, sedative herb that lowers blood pressure, relieves pain, stimulates bile flow, and relaxes spasms.
Medicinal Uses:	Internally for convulsive illnesses (such as epilepsy and tetanus), rheumatoid arthritis, vertigo, and numbness associated with liver disharmony.
Bibliography:	Encyclopedia of Herbs by Deni Bown. Copyright © 1995, 2001 Dorling Kindersley Limited. pp 220-221