Chrysosplenium americanum aka American Golden Saxifrage

Chrysosplenium americanum belongs to the saxifrage family, Saxifragaceae. Its common names include water carpet and water mat. It grows wild in eastern Canada and the United States. Its range includes the eastern and north-central United States. This is a plant of temperate regions. It is not native to Britain or Ireland. Wild plants grow near springs, small streams, and cold, wet ground.

This low perennial forms clumps that join into a dense carpet. It reaches about 0.33 feet [0.1 metres] tall. Its spread reaches about 1.6 feet [0.5 metres]. Creeping stems run across the ground and take root. These stems help the mat spread, though its extent remains limited. Below ground, the plant has many fine, fibrous roots. Its low form suits ground cover rather than a tall border role.

Flowers appear from April to May. Each flower has both male and female organs. Beetles and flies pollinate the flowers. The plant can also set seed with its own pollen. The supplied species evidence gives no flower colour or fruit details. It also gives no species-level description of the leaves. The RHS describes these traits for the genus, not this species.

Choose a shaded site with a steady supply of water. Light woodland shade suits it, though it can also grow without shade. It needs soil that stays wet but still drains. Sandy soil, loam, and clay can all support growth. It prefers acid soil and can grow in very acid ground. It also tolerates neutral and mildly alkaline soil. Plants For A Future lists USDA zones 3–7 for hardiness. Its creeping growth makes it useful in a bog garden. It can also provide ground cover in a woodland garden.

Propagate it by seed in spring or autumn, or divide clumps in spring. Sow seed in a cold frame with light shade. Keep the seed pot standing in shallow water. Grow young seedlings through their first winter under cold-frame cover. Plant them out after the last expected frost. Large divisions can go straight into their final sites. Smaller pieces benefit from pot culture until roots grow well. Plants For A Future records use as a salad spice. It gives no edible plant part and rates food value low. That source lists no known hazards or medicinal uses. This does not establish safety for people or pets. The supplied evidence identifies no specific pests or diseases.