Chinese Motherwort

Approximately four species of upright biennials and perennials make up this genus, which is distributed throughout temperate Eurasia. They are widely grown in herb gardens and are attractive in spring, when the divided, deeply veined foliage is at its best. Leonurus cardiaca was prescribed in ancient Greece for anxiety in pregnant women; hence the name "motherwort". Research has proved that it is effective in calming the heart and reduces the risk of thrombosis. There has been much confusion over the identity of motherworts used in Chinese medicine. Studies by Shiu Ying Hu and Harvard University in the 1970's concluded that L. heterophyllus was the same plant also known as Stachys artemisia; taxonomically, the correct name therefore became a combination of the two: L. artemisia. The differences between L. artemisia and L. sibiricus are small: the former has rather smaller flowers than the latter, with upper and lower lips about equal in length and undivided leaves on the upper part of the stem. However, some authorities regard L. heterophyllus and Stachys artemisia as synonyms of Leonurus sibiricus—in other words, all three entities are the same species. For this reason, and the fact that all motherworts are thought to have similar properties, L. artemisia is not described seperately here. The uses of L. artemisia were described 2000 years ago in the Shen Nong Ben Cao Jing; L. sibiricus (as L. heterophyllus) was first mentioned in the Illustrated Classic of the Materia Medica by Su Song (CE1061). Motherwort is unusual among Chinese herbs in being often prescribed as a "simple" (that is, not mixed with other herbs).

Erect biennial with branched stems, square in cross-section, bearing deeply veined, pinnately divided leaves, to 10cm (4in) long, which have 3-5 lobes in the upper part of the stem. Small 2-lipped, pink to off-white flowers, with upper lips longer than lower lips, appear in axillary whorls in summer , followed by black nutlets.

Common Name:	Chinese Motherwort
Botanical Name:	Leonurus sibiricus
Genus:	Leonurus
Family:	Lamiaceae
Native Location:	Siberia, China, Korea, and Taiwan
Cultivation:	Well-drained, moist soil in sun or partial shade.
Propagation:	By seed sown in spring; by division in spring or autumn (L. cardiaca).
Harvest:	Plants are cut when flowering, but before the seeds are set, and dried for infusions, liquid extracts, and tinctures (L. cardiaca), or in decoctions, pills, powders, and poultices (L. sibiricus). Seeds (L. sibiricus) are collected when ripe in autumn by drying the whole plant, and threshing and sifting it to remove seeds.
Height:	1m (3ft)
Width:	60cm (24in)
Hardiness:	Z4-8
Parts Used:	Whole plant (yi mu cao), seeds (chong wei zu)
Properties:	A bitter, diuretic herb that stimulates the circulation and uterus, lowers blood pressure, regulates menstruation, and clears toxins. It is also effective against bacterial and fungal infections. Seeds are slightly sweet and have similar actions but ar less effective as a diuretic and detoxicant.
Medicinal Uses:	Internally for eye problems related to the liver meridian (seeds); painful and excessive menstruation, postpartum bleeding (whole plants, seeds); edema, kidney complaints, kidney stones, eczema, and abscesses (whole plant). Not given to pregnant women.
Culinary Uses:	Young foliage is eaten as a vegetable. Roots are cooked with pork (China).
Bibliography:	The Encylopedia of Herbs by Deni Bown Copyright © 1995, 2001 Dorling Kindersley Limited pp 258-9