Houttuynia

Houttuynia cordata (Vietnamese: giấp cá), the sole species in the genus Houttuynia, is a flowering plant native to Japan, southern China and Southeast Asia, where it grows in moist, shady places.

Houttuynia is a herbaceous perennial plant growing to between 20 and 80 cm. The proximal part of the stem is trailing and produces adventitious roots, while the distal part of the stem grows vertically. The leaves are alternate, broadly heart-shaped, 4-9 cm long and 3-8 cm broad. Flowers are greenish-yellow, borne on a terminal spike 2-3 cm long with 4-6 large white basal bracts.

Cultivation
The plant grows well in moist to wet soil and even slightly submerged in water in partial or full sun. Plants can become invasive in gardens and difficult to eradicate. Propagation is via division.

Houttuynia in temperate gardens is usually in one of its cultivated forms, including: Chameleon (synonymous with H.c. 'Court Jester', H.c. 'Tricolour', H.c. 'Variegata') this variety is slightly less vigorous than the species and has leaves broadly edged in yellow and flecked with red; Flore Pleno has masses of white bracts and the vigour of the parent species.

Medicinal and culinary use
Grown as a leaf vegetable, particularly in Vietnam, where it is called giấp cá or diếp cá and is used as a fresh herbal garnish. The leaf has an unusual taste that is often described as fishy (earning it the nickname "fish mint"), so it is not enjoyed as universally as basil, mint, or other more commonly used herbs.

Houttuynia is also used in herbal medicine. The beverage dokudami cha (Japanese: ドクダミ茶; literally "Houttuynia cordata tea") is an infusion made from Houttuynia cordata leaves, Oolong tea leaves, and Job's Tears.

In the southwestern Chinese provinces of Yunnan, Guizhou, and Sichuan, roots are used as a root vegetable. English names include heartleaf and lizardtail.

Invasive Weed
Lizard Tail is an invasive species in many areas in the United States. Even the less vigorous forms will spread beyond an apt gardener's control if planted in any moderately moist soil. To prevent this, try planting in an old pot, sunk down into the garden soil.

References and external links

 * Flora of China: Houttuynia
 * Asian Vegetables (with photo)
 * Flora, The Gardener's Bible, ABC Publishing, Ultimo, NSW, Australia, 2006 ISBN 0 7333 1439 2

Houttuynia ドクダミ Houttuynia Giấp cá 鱼腥草