Trillium chloropetalum
Giant trillium
(c) Dawn Endico, some rights reserved (CC BY-SA) · licence
Family: Melanthiaceae · Type: Herb · Native
Trillium chloropetalum (Giant trillium) is a native California herb in the Melanthiaceae family, recognized by variable colored petals and erect orientation.
Giant trillium is a California native perennial found in the Klamath Ranges, northern Coast Ranges, Central Coast, and San Francisco Bay Area in moist redwood forest edges, chaparral, and canyon banks at elevations of 100 to 2,000 meters. Flowering from April to May, this plant produces remarkable flowers ranging from yellow to pink to dark purple, occasionally white, with erect petals 6.5 to 10 centimeters long and a sweet rose-like or spicy fragrance. Growing with stems 20 to 70 centimeters tall, it forms large, striking clumps with distinctive sessile leaves. Its broad leaves are 7 to 21 centimeters long and wide, rounded at the tip and often subtly mottled with brown-green spots. The fruit is an ovoid, red-purple pulpy structure with obscure six-sided angles.
Identification and appearance
Key characters: 2 sympatric species; key features are variable colored petals and erect orientation
Habitat and range
Habitat: Edges of redwood forest, chaparral, generally moist slopes, canyon banks in alluvial soils
Elevation: 100-2000 m
California counties: Sonoma, El Dorado, Alameda, Siskiyou, San Mateo, Santa Clara, Mendocino, San Benito, Shasta, Yuba, Humboldt, Contra Costa, Monterey, Lake, Marin, Tehama, Santa Cruz, Glenn, Napa, Madera, Santa Barbara, Butte, Placer, Del Norte, Nevada, Colusa
Bloom period
Trillium chloropetalum blooms Apr-May.
How to tell it apart
vs Pseudotrillium: Trillium leaves attach directly to stem and feel thin; Pseudotrillium leaves have short stalks and feel thick and leathery.; vs Lysimachia: Trillium has three leaves in one whorl; Lysimachia has multiple leaves in pairs or whorls along the stem.; vs Asarum: Trillium has three leaves above ground with a flower above; Asarum has two leaves at ground level with flower at base.; vs Scoliopus: Trillium has three broad leaves in a whorl; Scoliopus has two basal leaves with mottling.; vs Viola: Trillium has three leaves in a single whorl; Viola has heart-shaped leaves arising separately from the base.
Frequently asked questions
Is Trillium chloropetalum native to California?
Yes. Trillium chloropetalum is native to California (recorded as native).
When does Trillium chloropetalum bloom?
Trillium chloropetalum blooms Apr-May.
Where in California does Trillium chloropetalum grow?
Trillium chloropetalum occurs in Sonoma, El Dorado, Alameda, Siskiyou, San Mateo, Santa Clara, Mendocino, San Benito and other counties, at elevations of 100-2000 m.
What plant family does Trillium chloropetalum belong to?
Trillium chloropetalum is in the Melanthiaceae family, genus Trillium.
What habitat does Trillium chloropetalum grow in?
Trillium chloropetalum grows in Edges of redwood forest, chaparral, generally moist slopes, canyon banks in alluvial soils.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.