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Common Name: Rhubarb

General Information

Rheum rhaponticum is a perennial plant that can grow up to 1.20 metres tall.
It has edible, medicinal and miscellaneous uses.

Known Hazards

The leaves contain high concentrations of oxalic acid[, ]. Oxalic acid can lock up certain minerals (especially calcium) in the body, leading to nutritional deficiency. Cooking the plant will reduce the concentration of oxalic acid. Another report says that the leaves have the same concentration of oxalic acid in the stems as they do in the leaves and it is not the oxalic acid that makes them poisonous. It says that any toxic properties of the leaves is more likely to be due to the presence of glycosides[]. 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

Europe to E. Asia - Siberia.

Habitat

Wet mountain rocks in Europe[].

Properties

Edibility Rating
Medicinal Rating
Habit	Perennial
Height	1.20 m
Pollinators	Wind
Cultivation Status	Wild

Cultivation Details

Prefers a deep, fertile, moderately heavy, humus rich, moisture retentive, well-drained soil in sun or semi-shade[]. Shade tolerant[], but plants prefer a sunny position[]. Grows well in heavy clay soils.
Hardy to at least -20°c[].
This species is probably a parent of the cultivated rhubarb, R. x cultorum[].
Plants in this genus seem to be immune to the predations of rabbits[].
Hybridizes freely with other members of this genus[].

Edible Uses

Leaf stem - raw or cooked[, , ]. An acid flavour, they are used as a fruit substitute in tarts etc[].
The young flower pouch, harvested before the flowers open, is said to form a dish of great delicacy[].

Medicinal

Rhubarb has a long and proven history of herbal usage, its main effect being a positive and balancing effect upon the whole digestive system. It is one of the most widely used herbs in Chinese medicine[]. The main species used is R. palmatum. Though the chemistry varies slightly, this species is used interchangeably[]. Another report says that this species contains only small quantities of the medicinally active compounds and so it is only used as a mild laxative[].
The root is anticholesterolemic, antiseptic, antispasmodic, antitumor, aperient, astringent, cholagogue, demulcent, diuretic, laxative, purgative, stomachic and tonic[, , , , , ]. Small doses act as an astringent tonic to the digestive system, whilst larger doses act as a mild laxative[]. The root is taken internally in the treatment of chronic constipation, diarrhoea, liver and gall bladder complaints, haemorrhoids, menstrual problems and skin eruptions due to an accumulation of toxins[]. This remedy is not prescribed for pregnant or lactating women, nor for patients with intestinal obstruction[]. Externally, the root is used in the treatment of burns[]. The roots are harvested in October from plants that are at least six years old, they are then dried for later use[].
A homeopathic remedy is prepared from the dried root[]. This is used especially in the treatment of diarrhoea in teething children[].

Other Uses

Plants can be grown for ground cover when spaced about 1.8 metres apart each way[].

Propagation

Seed - best sown in autumn in a shaded cold frame[]. The seed can also be sown in spring in a cold frame. When large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse or cold frame for their first winter, planting them out in the spring.
Division in early spring or autumn[, ]. Divide up the rootstock with a sharp spade or knife, making sure that there is at least one growth bud on each division. 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.