Rheum nobile
Hook.f.&Thoms.
Sikkim Rhubarb
iNaturalist· cc-by-nc
(c) Letro Letro, some rights reserved (CC BY-NC), uploaded by Letro Letro
iNaturalist· cc-by-nc
(c) Pema yangden, some rights reserved (CC BY-NC), uploaded by Pema yangden
iNaturalist· cc-by-nc
(c) 刘光裕 Liu Guangyu, some rights reserved (CC BY-NC), uploaded by 刘光裕 Liu Guangyu
Description
Rheum nobile is a PERENNIAL growing to 1.5 m (5ft) by 1 m (3ft 3in). See above for USDA hardiness. It is hardy to UK zone 7. It is in flower from July to August, and the seeds ripen from August to September. The species is hermaphrodite (has both male and female organs) and is pollinated by Wind. Suitable for: medium (loamy) and heavy (clay) soils, prefers well-drained soil and can grow in heavy clay soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.
Edible Uses
Leaf stem - raw or cooked. Pleasantly acid, this is a commonly used vegetable where it grows wild.
Medicinal Uses
Antiemetic Astringent Carminative Depurative Diuretic Laxative. The root is astringent, carminative, depurative, diuretic, purgative and tonic. Small doses act as an astringent tonic to the digestive system, whilst larger doses act as a mild laxative. The flowering stem is used in Tibetan medicine, it is said to have a sour taste and a heating potency. It is antiemetic, diuretic and laxative. It is used in the treatment of swellings and fullness of the abdomen as well as to rid the body of retained fluids.
Known Hazards
Although no specific mention has been seen for this species, the leaves of some if not all members of this genus contain significant quantities of oxalic acid and should not be eaten in any quantity. Oxalic acid can lock up certain minerals in the body, especially calcium, leading to nutritional deficiency. The content of oxalic acid will be reduced if the plant is cooked. 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.
Distribution
E. Asia - Himalayas from Nepal to S.E. Tibet.
Where It Grows
TEMPERATE ASIA: China (Xizang Zizhiqu (south)) TROPICAL ASIA: Bhutan, India (Sikkim), Nepal, Myanmar (north)
Cultivation
Prefers a deep, fertile, moderately heavy, humus rich, moisture retentive, well-drained soil in sun or semi-shade. Grows well in heavy clay soils. A very ornamental plant, it is hardy to about -15°c. Plants have proved very difficult to grow in cultivation in Britain. Plants in this genus seem to be immune to the predations of rabbits. Hybridizes freely with other members of this genus.
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.
Other Uses
An ornamental plant hardy to about -15°c.
