Pacific Trillium
Trillium ovatum
Last reviewed: September 2026
Trillium ovatum, or Pacific trillium, is a woodland forb that blooms white three-petaled flowers from April through June in shaded, moist forest understories.
Toxicity unknown
Pacific Trillium (Trillium ovatum) is not listed by the ASPCA Animal Poison Control Center (opens in new tab) or the other sources we check, so we have no verdict for it either way. Absence from those lists is not a clearance. If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.
Light
part shade
Water
medium
Size
6"–18" H × 6"–12" W
Bloom
Apr, May, Jun
Native to
CA, OR, WA
Pollinators
bees, beetles
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Pacific trillium is a woodland wildflower with distinctive three-petaled white flowers that bloom in spring. This low-growing perennial prefers shaded areas and goes dormant in summer, disappearing completely until the following spring.
Growing Pacific Trillium
Grow Pacific Trillium in part shade and medium water. Mature plants reach 6 to 18 inches tall and spread 6 to 12 inches wide. Expect low maintenance to keep it looking intentional in a front yard.
In an HOA neighborhood
Pacific Trillium takes more care to keep looking intentional in a front yard. Maintenance level: low. Consider it for backyard or mid-zone beds rather than the street edge.
Works well in: backyard only.
- Completely dormant and invisible for most of growing season
- Wild woodland appearance may look unkempt
Wildlife value
The flowers attract bees and beetles during the spring blooming period. As a woodland species, it provides early season nectar when few other plants are flowering.
Common questions
- When does Trillium ovatum bloom?
- Pacific trillium typically flowers from April through June, producing white flowers that often fade to pink or purple as they age.
- What pollinates Trillium ovatum?
- Bees and beetles are the main pollinators, visiting the flowers in spring for pollen and nectar.
- What growing conditions does Trillium ovatum prefer?
- It grows best in part shade with medium soil moisture, favoring humus-rich, well-drained forest soil that stays cool and moist in spring.
- Is Trillium ovatum evergreen?
- No, it is deciduous. The above-ground growth dies back to an underground rhizome by mid to late summer after flowering and seed set.
- Is Pacific Trillium HOA-friendly?
- Pacific Trillium takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.
These answers were drafted with an AI model from this plant's data. Verify care details with a local expert.
Native range data from vouchered herbarium specimen records and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.
If something looks wrong
Common plant problems, and what to check first
These come up on almost any plant. Each guide lists the likely causes in the order they are worth ruling out, with one thing to check before you act on any of them, and links to the source it came from.
- It is dying right after planting
- Leaves turning yellow
- Wilting even though I watered it
- Brown crispy leaf tips
- Bugs on the plant
Ready to grow Pacific Trillium? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.
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