Trillium ovatum aka Pacific Trillium

Trillium ovatum is a woodland perennial from western North America. It belongs to the family Melanthiaceae and grows from underground rhizomes. Its names include western wakerobin and Pacific trillium. Its native range runs from western Canada into California. Records also place it inland in Idaho, Montana, Wyoming and Colorado. It grows in rich woods, including damp and boggy sites. Its habitats reach from low valleys into mountain woods.

In gardens, plants reach about 1.6 feet [0.5 metres] tall and wide. They form clumps with upright stems and lose their leaves seasonally. The stems have a reddish cast. Each bears three dark green leaves with a diamond-like shape. Deep veins mark the leaf surface. Short flower stalks rise above this ring of leaves. The fragrant flowers open white in spring. Their petals spread out and curve back. As the blooms age, they turn reddish pink.

Give this plant light shade and soil rich in humus. The RHS also lists full shade as suitable. Plants For A Future favours dappled shade rather than deep shade. Keep the soil moist, but allow excess water to drain. Loam and clay are suitable soil types. A neutral to slightly acid soil suits it best. Choose a sheltered spot beneath shrubs or in woodland beds. Avoid neighbours that could crowd out the clumps. Add a mulch of leaf mould each autumn. The RHS rates its hardiness H5. Plants For A Future lists USDA zones 4–8.

This trillium suits cottage gardens, shaded borders and woodland planting. Its spring flowers add interest above the dark leaves. It can also grow beneath roses and other shrubs. The RHS gives a maturity range of two to five years. Seed-grown plants may need several years before they flower. Sow ripe seed in pots within a shaded cold frame. Divide the rhizomes after flowering to raise more plants. It needs no pruning. Aphids, slugs and snails may attack it. The RHS reports few disease problems.

Plants For A Future records cooked leaves as an occasional food. It gives the plant a low edible-use rating. The same source lists no known hazards. That does not establish safety for every person or pet. It also records traditional uses for eyes, boils and childbirth. These records do not establish safe or effective treatments. Its medicinal rating is low, and no other uses are recorded. Plants For A Future does not flag it as weedy.