Rheum rhaponticum

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Rheum rhaponticum
Light:Full Sun Part Shade
Moisture:Mesic
Hardiness:3
Soil pH:5.6-8.4
Height:4'
Blooms:Early Summer
Native to:
Edible Rating:PFAF Edibility RatingPFAF Edibility Rating
Medicinal Rating:PFAF Medicinal RatingPFAF Medicinal Rating
Tea:Yes
Poisonous

Rheum rhaponticum (common name: rhubarb)

Propagation: Seed - best sown in autumn in a shaded cold frame[1]. 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[2][3]. 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.

Cultivation: Prefers a deep, fertile, moderately heavy, humus rich, moisture retentive, well-drained soil in sun or semi-shade[1]. Shade tolerant[4], but plants prefer a sunny position[5]. Grows well in heavy clay soils.

Hardy to at least -20°c[1].

This species is probably a parent of the cultivated rhubarb, R. x cultorum[1].

Plants in this genus seem to be immune to the predations of rabbits[6].

Hybridizes freely with other members of this genus[1].

Range: Europe to E. Asia - Siberia.

Habitat: Wet mountain rocks in Europe[7].

Edibility: Leaf stem - raw or cooked[2][8][9]. An acid flavour, they are used as a fruit substitute in tarts etc[8].

The young flower pouch, harvested before the flowers open, is said to form a dish of great delicacy[8].

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[10]. The main species used is R. palmatum. Though the chemistry varies slightly, this species is used interchangeably[10]. 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[11].

The root is anticholesterolemic, antiseptic, antispasmodic, antitumor, aperient, astringent, cholagogue, demulcent, diuretic, laxative, purgative, stomachic and tonic[12][5][13][14][15][10]. Small doses act as an astringent tonic to the digestive system, whilst larger doses act as a mild laxative[16]. 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[10]. This remedy is not prescribed for pregnant or lactating women, nor for patients with intestinal obstruction[10]. Externally, the root is used in the treatment of burns[10]. The roots are harvested in October from plants that are at least six years old, they are then dried for later use[12].

A homeopathic remedy is prepared from the dried root[16]. This is used especially in the treatment of diarrhoea in teething children[16].

Usage: Plants can be grown for ground cover when spaced about 1.8 metres apart each way[17].

Pollinators: Wind

Soil: Can grow in medium and heavy soils.

Drainage: Prefers well drained soil.

Seed Ripens: Mid Summer

Flower Type: Hermaphrodite

Heavy Clay: Grows in heavy-clay soils.

Known Hazards: The leaves contain high concentrations of oxalic acid[18][19]. 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 say

Links

References

  1. 1.0 1.1 1.2 1.3 1.4 Huxley, Anthony. The New Royal Horticultural Society Dictionary of Gardening. MacMillan Press, 1992.
  2. 2.0 2.1 Chittendon, Fred. RHS Dictionary of Plants. Oxford University Press, 1951.
  3. Sanders, Thomas. Popular Hardy Perennials. Collingridge, 1926.
  4. Bryan, John and Coralie Castle. Edible Ornamental Garden. Pitman Publishing, 1976.
  5. 5.0 5.1 Thompson, Robert. The Gardener's Assistant. Blackie and Son, 1878.
  6. Thomas, Graham. Perennial Garden Plants. J. M. Dent & Sons, 1990.
  7. Tutin, Tom et al.. Flora Europaea. Cambridge University Press, 1964.
  8. 8.0 8.1 8.2 Hedrick, Ulysses. Sturtevant's Edible Plants of the World. Dover Publications, 1972.
  9. Heywood, Vernon. Flowering Plants of the World. Oxford University Press.
  10. 10.0 10.1 10.2 10.3 10.4 10.5 Bown, Deni. Royal Horticultural Society Encyclopaedia of Herbs and Their Uses. Dorling Kindersley, 1995.
  11. Phillips, Roger. Herbs. Pan Books, 1990.
  12. 12.0 12.1 Grieve, Margaret. A Modern Herbal. Penguin, 1984.
  13. Schery. Robert. Plants for Man. Prentice Hall, 1972.
  14. Usher, George. A Dictionary of Plants Used by Man. Constable, 1974.
  15. Hill, Albert. Economic Botany. The Maple Press, 1952.
  16. 16.0 16.1 16.2 Castro, Miranda. The Complete Homeopathy Handbook. Macmillan, 1990.
  17. Thomas, Graham. Plants for Ground Cover. Everyman, 1990.
  18. Nicholson, Barbara and Stephen Harrison. The Oxford Book of Food Plants. Oxford University Press, 1975.
  19. Cooper, Marion. Poisonous Plants in Britain and their Effects on Animals and Man. The Stationery Office, 1984.