Epilobium ravenii

California willowherb

Family: Onagraceae · Type: Herb · Native

Epilobium ravenii (California willowherb) is a native California herb in the Onagraceae family, recognized by small white flowers and dry habitat.

California willowherb is a native annual herb found in the Klamath Ranges, northern California, Sierra Nevada, northern Sierra Nevada foothills, Sacramento Valley, central western California, and Transverse Ranges at elevations of 20 to 1,900 meters in dry, open, and disturbed areas. Flowering from April to August, this plant produces white flowers 1.8 to 3 millimeters long with delicate petals. Growing with slender stems up to 45 centimeters tall, it has a taproot and becomes slightly peeling near the base. Its leaves are primarily sublinear to lanceolate, often folded along the midrib, with basal pairs opposite and upper leaves clustered and measuring 5 to 30 millimeters long. The fruit is a slender capsule 12 to 20 millimeters long, sparsely covered in fine hairs.

Identification and appearance

Key characters: 31 sympatric species, small white flowers and dry habitat help distinguish

Habitat and range

Habitat: Dry, open, disturbed areas, roadsides

Elevation: 20-1900 m

California counties: Marin, Lake, Napa, Yolo, Shasta, Amador, Trinity, Plumas, Tehama, Tuolumne, Ventura, Monterey, Santa Cruz, Humboldt, Sonoma, Tulare, Merced, Santa Clara, Los Angeles, Mariposa, Butte, El Dorado, San Mateo, Colusa, Fresno, Calaveras, Del Norte, Mendocino, Nevada

Outside California: to British Columbia, Idaho, Arizona, northwestern Mexico

Bloom period

Epilobium ravenii blooms Apr-Aug.

How to tell it apart

vs Penstemon: Epilobium has 4 notched petals and opposite leaves; Penstemon has 5-lobed tubular flowers (snapdragon family).; vs Gambelia: Epilobium has 4 notched petals; Gambelia has 5-lobed tubular snapdragon-like flowers.; vs Fuchsia: Epilobium has notched petals spreading flat; Fuchsia has dangling tubular flowers with protruding stamens.; vs Keckiella: Epilobium has 4 notched petals; Keckiella has 5-lobed tubular snapdragon-like flowers.; vs Diplacus: Epilobium has 4 notched petals; Diplacus has 5-lobed tubular monkey flowers.

Frequently asked questions

Is Epilobium ravenii native to California?

Yes. Epilobium ravenii is native to California (recorded as native).

When does Epilobium ravenii bloom?

Epilobium ravenii blooms Apr-Aug.

Where in California does Epilobium ravenii grow?

Epilobium ravenii occurs in Marin, Lake, Napa, Yolo, Shasta, Amador, Trinity, Plumas and other counties, at elevations of 20-1900 m.

What plant family does Epilobium ravenii belong to?

Epilobium ravenii is in the Onagraceae family, genus Epilobium.

What habitat does Epilobium ravenii grow in?

Epilobium ravenii grows in Dry, open, disturbed areas, roadsides.

Related species

Other California species in the same genus, family, or bioregion.

All Epilobium species · All Onagraceae

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.