Common Name: Himalayan Knotweed

General Information

Koenigia polystachya is a much-branched,perennial plant with stems that become more or less woody and persist; it can grow 80 - 100cm tall[].
The plant is harvested from the wild for local use as a food. It is sometimes grown as an ornamental, where it can be used to form a ground cover.

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 - Himalayan regions of Afghanistan, Pakistan, India, Nepal, Bhutan, southern China

Habitat

Forests, shrubberies and open slopes, often gregarious; at elevations from 2,000 - 4,500 metres[, ].

Properties

Edibility Rating
Other Uses Rating
Habit	Perennial
Height	1.80 m
Growth Rate	Fast
Cultivation Status	Ornamental, Wild

Cultivation Details

This is a moderately cold-hardy plant, being able to tolerate temperatures down to around -20°c when fully dormant[].
Succeeds in an ordinary garden soil[] but prefers a moisture retentive not too fertile soil in sun or part shade[]. Repays generous treatment[].
A vigorously spreading plant, it is only really suitable for large areas of ground[].
Plants are easily mistaken for Koenigia campanulata (Hook.f.) T.M.Schust. & Reveal[].
Plants seem to be immune to the predations of rabbits[].

Edible Uses

Leaves - cooked[].

We have no specific information for this species, but the seed of most, if not all, members of the genus is edible both raw and cooked, and is potentially a good source of amino acids. Unfortunately the seed is also usually rather small and fiddly to utilize[].

Medicinal

None known

Agroforestry Uses:

Plants are very vigorous and can be grown for ground cover, succeeding even on the verges of streams[]. They are best spaced about 1.2 metres apart each way[].

Other Uses

None known

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.
Division in spring or autumn. Very easy, larger divisions can be planted out direct into their permanent positions. We have found that it is better to pot up the smaller divisions and grow them on in light shade in a cold frame until they are well established before planting them out in late spring or early summer.