Epimedium sagittatum

Epimedium sagittatum is a perennial in the barberry family, Berberidaceae. Its common names include Yin Yang Huo and horny goat weed. Kew places its native range in central and southern China. Plants for a Future also lists Taiwan within its distribution. It grows in damp, shaded bamboo groves on hillsides. Other sites include moist woods and cracks in cliffs. These habitats suit its use in shaded garden beds.

Plants reach about 1.6 feet (0.5 metres) tall. Their spread reaches about 1.3 feet (0.4 metres). Rhizomes creep just beneath the soil and help form ground cover. The fine roots occupy the upper 1 foot (0.3 metres). This shallow root system is a key part of its form. The plant fits woodland gardens, shaded edges, and rock gardens. It also suits wild gardens where its ground cover has room.

Flowers appear from May to June, and bees pollinate them. Each flower has both male and female organs. Yet a plant cannot set seed with its own pollen. Gardeners need more than one clone for seed production. Nearby species may cross with it, so seedlings can be hybrids. Sow fresh seed in a cold frame in late summer. Stored seed should go into a cold frame early in the year. Division offers another way to raise plants without relying on seed.

Light, dappled woodland shade gives the best growing conditions. Use fertile soil with plenty of humus and good drainage. A moist, peaty loam suits it well. It also grows in sandy soil or clay. It accepts mildly acid, neutral, and mildly alkaline ground. Although it prefers moisture, it can cope with dry tree shade. Plants for a Future lists USDA zones 5–9. It reports cold tolerance to at least 5°F (−15°C). Late frost can still kill the fresh spring growth.

Plants for a Future records cooked young shoots and leaves as food. Its account calls for soaking them before boiling. It also records traditional medicinal uses for the whole plant. These include use for joint pain and breathing complaints. That record does not establish that such treatments work. Excess use can cause vomiting, dizziness, thirst, and nosebleeds. Its food use should therefore not imply unrestricted safety. Plants for a Future does not flag it as weedy.