Common Name: Bistort

General Information

Polygonum bistorta is a herbaceous perennial plant growing from a rhizomatous rootstock; it produces a cluster of stems around 50 - 80cm tall[].
Bistort was formerly cultivated as a medicinal and edible plant[], though it is rarely cultivated at present.The planIt is sometime 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

, ,

Range

Widespread through temperate Eurasia, but absent from Scandanavia and central Asia; N. Africa - Morocco

Habitat

Damp meadows and by water, especially on acid soils[, ]. Hilly grasslands, meadows; at elevations from 800 - 3,000 metres[]

Properties

Edibility Rating
Medicinal Rating
Other Uses Rating
Habit	Perennial
Height	0.60 m
Pollinators	Insects
Cultivation Status	Wild

Cultivation Details

This is a very cold-hardy plant, being able to tolerate temperatures down to around -25 to -30°c when fully dormant[, ].
Succeeds in an ordinary garden soil[] but prefers a moisture retentive not too fertile soil in sun or part shade[]. The plant repays generous treatment[].
Plants are somewhat spreading, forming quite extensive colonies[] especially in low-lying pastures[]. They seem to be immune to the predations of rabbits[].

Edible Uses

Leaves - raw or cooked[, , , ]. One report says that they are rather bitter[], but we have found them to have a fairly mild flavour, especially when the leaves are young, though the texture is somewhat chewy when they are eaten raw[, ]. They make an excellent substitute for spinach[].
In Northern England the leaves are an ingredient of a bitter Lenten pudding, called Easter ledger pudding, that is eaten at Lent[].
The leaves are available from late winter in most years and can be eaten until the early autumn though they become much tougher as the season progresses[].
The leaves are a good source of vitamins A and C[], a nutritional analysis is available[].

Seed - raw or cooked[]. The seed is very small and rather fiddly to utilize[].

Root - raw or cooked[, , ]. Rich in starch and tannin, it is steeped in water and then roasted in order to reduce the tannin content[, ]. It is then said to be a tasty and nutritious food[]. The root has also been boiled or used in soups and stews[] and can be dried then ground into a powder and used in making bread[]. The root contains 30% starch, 1% calcium oxalate and 15 - 36% tannin[].

Medicinal

Bistort is one of the most strongly astringent of all herbs and it is used to contract tissues and staunch blood flow[].
The root is powerfully astringent, demulcent, diuretic, febrifuge, laxative and strongly styptic[, ]. It is gathered in early spring when the leaves are just beginning to shoot, and then dried[]. It is much used, both internally and externally, in the treatment of internal and external bleeding, diarrhoea, dysentery, cholera etc[, , , , , , ]. It is also taken internally in the treatment of a wide range of complaints including catarrh, cystitis, irritable bowel syndrome, peptic ulcers, ulcerative colitis and excessive menstruation[, ].
Externally, the root makes a good wash for small burns and wounds, and is used to treat pharyngitis, stomatitis, vaginal discharge, anal fissure etc[, ]. A mouth wash or gargle is used to treat spongy gums, mouth ulcers and sore throats[].

The leaves are astringent and have a great reputation in the treatment of wounds[].

Other Uses

The roots contain up to 21% tannin[].

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.