He Shou Wu, Tuber fleeceflower

Polygonum multiflorum

Physical Characteristics

Polygonum multiflorum is a PERENNIAL CLIMBER growing to 4.5 m (14ft 9in). See above for USDA hardiness. It is hardy to UK zone 7. It is in flower from September to October, and the seeds ripen from October to November. The species is hermaphrodite (has both male and female organs) and is pollinated by Insects. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils. 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.

Distribution

E. Asia - China.

Habitats

Woodland Garden Dappled Shade; Shady Edge;

Edible Uses

Edible Parts: Flowers Leaves Root Seed Edible Uses: Leaves - raw or cooked. Seed - raw or cooked. It is rather small and fiddly to utilize[105]. Flowers[179]. No more details are given. Root - cooked[2, 177]. It should be washed several times in order to leech out the bitterness[179]. This process will also remove many of the vitamins and minerals from the roots[K]. A famine food, it is only used when all else fails[105].

Medicinal Uses

Antibacterial Anticholesterolemic Antipyretic Antispasmodic Antitumor Astringent Cardiotonic Demulcent Deobstruent Hypoglycaemic Laxative Sedative Tonic Urinary He Shou Wu is considered to be one of the most important of the Chinese herbal tonics and is widely used in that country[218]. It is said to restore vitality and virility[174], working especially on the liver and the reproductive, urinary and circulatory systems[238]. Some care should be exercised, however, since excessive doses can cause skin rash and numbness of the extremities[238]. The roots and stems are antibacterial, anticholesterolemic, antispasmodic, astringent, cardiotonic, demulcent, depurative, hypoglycaemic, laxative, sedative, tonic[116, 147, 174, 176, 238, 279]. The roots are taken internally in the treatment of menstrual and menopausal complaints, constipation in the elderly, swollen lymph glands and high cholesterol levels[238]. They are very effective in reducing high cholesterol levels in the blood and increase blood sugar levels[254]. Externally, they are used to treat ringworm, bleeding wounds and sores[238]. The roots are harvested in the autumn, preferably from plants 3 - 4 years old, and are dried for later use[238]. The leaves and roots tonify the liver and kidneys, fortify the blood, strengthen the muscles and prevent premature greying of the hair[218]. The stem is deobstruent and sedative[218]. It is taken internally in the treatment of insomnia and neurasthenia whilst it is applied externally to ringworm[176, 238]. The stems are harvested in late summer or early autumn and are dried for later use[238]. Extracts of the plant have shown antipyretic, antitumour, hypoglycaemic and sedative activity[218].

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[238].