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Common Name:

General Information

Polygonum nepalense is an annual plant that can grow up to 0.30 metres tall.
It is harvested from the wild for local use as a food, medicine and source of materials.

Known Hazards

Although no specific mention has been made for this species, there have been reports that some members of this genus can cause photosensitivity in susceptible people.
Many species also contain oxalic acid (the distinctive lemony flavour of sorrel) - whilst not toxic this substance can bind up other minerals making them unavailable to the body and leading to mineral deficiency. Having said that, a number of common foods such as sorrel and rhubarb contain oxalic acid and the leaves of most members of this genus are nutritious and beneficial to eat in moderate quantities. Cooking the leaves will reduce their content of oxalic acid. People with a tendency to rheumatism, arthritis, gout, kidney stones or hyperacidity should take especial caution if including this plant in their diet since it can aggravate their condition[].

Botanical References

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Range

E. Asia - China, Japan, Korea, Himalayas.

Habitat

Usually common in damp shaded situations, 1700 - 2000 metres in Srinagar. Damp woods in mountains all over Japan[]. Exposed rocky slopes, 1200 - 4000 metres in Nepal[].

Properties

Edibility Rating
Medicinal Rating
Habit	Annual
Height	0.30 m
Cultivation Status	Wild

Cultivation Details

We have very little information on this species and do not know if it is hardy in Britain, though it should succeed as a spring-sown annual in this country. The following notes are based on the general needs of the genus.
Succeeds in an ordinary garden soil[] but prefers a moisture retentive not too fertile soil in sun or part shade[]. Repays generous treatment[].
Plants seem to be immune to the predations of rabbits[].

Edible Uses

Tender young leaves and shots - raw or cooked as a vegetable[, ].
Seed - raw or cooked. It is rather small and fiddly to utilize.

Medicinal

A juice of the root is used in the treatment of fevers[]. A paste of the root is used as a poultice on fresh wounds[].

Other Uses

The squeezed plant is used for washing clothes[].

Propagation

Seed - sow spring in a cold frame. Germination is usually free and easy. When they are large enough to handle, prick the seedlings out into individual pots and plant them out in the summer if they have reached sufficient size. If not, overwinter them in a cold frame and plant them out the following spring after the last expected frosts.