© Elijah Disrude, some rights reserved (CC-BY-NC) · iNaturalist
Pseudotrillium spp.
brook wakerobin
Pacific Northwest (Oregon and California)
Overview
Pseudotrillium is a genus in the family Melanthiaceae containing a single species, P. rivale, the brook wakerobin, once classified within Trillium. It is a low, rhizomatous, spring-flowering woodland perennial growing 4-12 inches (10-30 cm) tall. Three broadly oval, stalked leaves are carried in a whorl atop the stem, each 1.5-3 inches (4-8 cm) long and marked with faint mottling when young. Unlike true Trillium, the single flower is held on a slender stalk (pedicel) that lifts it above the leaves. Each flower has three white to pale pink petals 0.5-1 inch (12-25 mm) long, often spotted or streaked with maroon toward the base. Flowering occurs in early spring, after which the plant sets a berry-like capsule and dies back to the rhizome by summer, behaving as a spring ephemeral. The genus is restricted to a small area of the Pacific Northwest and grows along shaded, moist streambanks. It is slow to establish and slow to recover from disturbance once settled.
Native Range
Pseudotrillium rivale is endemic to a small region of the Klamath-Siskiyou Mountains in southwestern Oregon and northwestern California. It grows on shaded, rocky streambanks and seepage slopes, often over serpentine soils, in moist coniferous and mixed woodland.Suggested Uses
Grown in shaded rock gardens, woodland borders, and alpine or trough plantings by collectors of Trillium relatives. Its small size suits the front of moist, shaded beds. It pairs with ferns, hellebores, and other spring woodland plants.How to Identify
Appearance
Size & Dimensions
Height4" - 1'
Width/Spread6" - 1'
Reaches mature size in approximately 4 years
Bloom Information
Flowering occurs in early spring, often March to April, with each plant producing a single, long-lasting flower. Bloom appears soon after the foliage emerges. By early summer the plant goes dormant.
Detailed Descriptions
Flower Description
white to pale pink with maroon spotsFoliage Description
green with faint mottlingGrowing Conditions
Sun Requirements
Requires 2-5 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Grow Pseudotrillium in part to full shade in humus-rich, gritty, consistently moist but well-drained soil. The genus suits cool woodland and shaded rock gardens and tolerates serpentine and slightly acidic to neutral soils. Keep the root zone moist during spring growth, allowing it to dry somewhat during summer dormancy. A mulch of leaf mold conserves moisture and feeds the rhizome. Plants are slow-growing and may take several years to settle and flower freely, so they are left undisturbed once planted. Slugs and snails can damage the emerging shoots.Pruning
No pruning is required for Pseudotrillium. Spent foliage is left to die back naturally, as it feeds the rhizome for the following season. Damaged or yellowing leaves can be removed once dormancy begins.Container Growing
Suitable for container growing
Minimum container size: 2 gallons