Leonurus macranthus

Leonurus macranthus is in the mint family, Lamiaceae. It is a perennial, a plant that lives for years. It is native to China, Japan, Korea, and Manchuria. It is not native to Britain or Ireland. In Japan, it grows among grasses and thickets on hills. Chinese records also place it in shade in Kiangnan. Other records place it on grassy slopes in northeastern China. It grows in thickets there too. These sites include Hebei, Jilin, and Liaoning.

The plant grows about 3.3 feet (1 metre) tall. The account gives no width for a full-grown clump. It blooms from July through September. Each flower has both male and female organs. Bees move pollen between the flowers. Seeds ripen from September through October. The sources do not state the flower colour or fruit shape. Nor do they describe the leaves or stems.

PFAF says it can grow in sun and light shade. It lists sunny edges of woods and spots with patchy shade. The plant prefers soil that stays moist. It can grow in sand, loam, and clay soils. PFAF also lists soils that are mildly acid or mildly alkaline. Neutral soil suits it too. But PFAF stresses how little growing data it has for this species. Some of its notes draw on the needs of the genus. Its range suggests it may survive outdoors in Britain. This is a cautious forecast, not proof of hardiness. The evidence gives no firm hardiness zone.

PFAF describes how to grow plants from seed in spring. One way is to start seedlings in a cold frame. Move them to their own pots when large enough to handle. The account then suggests planting them out in summer. With enough seed, you can also sow outdoors. You can split clumps in spring or autumn too. Large pieces can go straight into their final site. Keep small pieces in pots until their roots grow well.

PFAF lists leaves and shoots as parts you can eat. It says to cook the shoots. It gives no method for preparing the leaves. Its food-use rating is low: one out of five. It records past use as a tonic, including for problems after childbirth. This does not prove that it works or is safe. PFAF reports no known hazards. That does not prove the plant is harmless. The supplied evidence names no pests or diseases. It records no other uses. It flags no risk of the plant becoming a weed.