This species has previously been included within Dioscorea septemloba Thunb., from Japan, but it is now thought that Dioscorea septemloba should be restricted to Japanese material and the Chinese plants be treated as a distinct species, Dioscorea spongiosa[].

Common Name:

General Information

Dioscorea spongiosa is a perennial climbing plant growing from a much-branched, spreading, horizontal rhizome around 20 - 50mm thick; it produces vigorous annual stems that twine to the left. The stems scramble over the ground and twine into nearby vegetation[].
The plant is harvested from the wild for use in tradional Chinese medicine.

Known Hazards

None known

Botanical References

Range

E. Asia - southeast China

Habitat

Open forests, scrub forests; at elevations from 400 - 800 metres[].

Properties

Medicinal Rating
Habit	Perennial Climber
Height	0.00 m
Self-fertile	No

Cultivation Details

Not known

Edible Uses

None known

Medicinal

An important traditional medicine[].
The dried rhizome is used to remove turbid damp. and to relieve rheumatic conditions. The iIndications for its used are gonorrhea with a whitish discharge from the urethra; excessive leucorrhoea; ulcers caused by damp heat; arthralgia of the lumbar spine and knees[].

The roots of most, if not all, members of this genus, contains diosgenin[, ]. This is widely used in modern medicine in order to manufacture progesterone and other steroid drugs. These are used as contraceptives and in the treatment of various disorders of the genitary organs as well as in a host of other diseases such as asthma and arthritis[].

Other Uses

None known

Propagation

Seed - sow early spring to mid spring in a sunny position in a warm greenhouse and only just cover. It germinates in 1 - 3 weeks at 20°c[]. Prick out the seedlings as soon as they are large enough to handle and grow on in a greenhouse for their first year. Plant out in late spring as the plant comes into new growth.
Basal stem cuttings in the summer[].
Division in the dormant season, never when in growth[]. The plant will often produce a number of shoots, the top 5 - 10 cm of the root below each shoot can be potted up to form a new plant whilst the lower part of the root can be eaten[].
Tubercles (baby tubers) are formed in the leaf axils. These are harvested in late summer and early autumn when about the size of a pea and coming away easily from the plant. They should be potted up immediately in individual pots in an unheated greenhouse or cold frame, covering them with about 10mm of soil. Protect them from mice etc and keep the soil moist but not wet. They should come into growth in the spring, plant them out in early summer when in active growth[].