Epilobium glaberrimum subsp. glaberrimum
Photo: parent species Epilobium glaberrimum · no rights reserved · CC0
Family: Onagraceae · Type: Herb · Native
Epilobium glaberrimum subsp. glaberrimum is a native California herb in the Onagraceae family, recognized by but glaucous coating completely diagnostic.
Smooth willowherb is a California native perennial found in the Klamath Ranges, northern Coast Ranges, Cascade Ranges, Sierra Nevada, Transverse Ranges, Peninsular Ranges, Warner Mountains, and northern White and Inyo Mountains in well-drained gravelly soils, streambanks, and roadsides at elevations of 150 to 3,000 meters. Flowering from June to September, this plant produces rose-purple to pink or white flowers 5 to 10 millimeters long. Growing with branched stems 20 to 85 centimeters tall, it develops a distinctive upright habit. Its leaves are narrowly lanceolate, measuring 20 to 70 millimeters long, arranged along the stem. The elongated fruit capsules reach 45 to 75 millimeters in length, extending well beyond the delicate flower clusters.
Identification and appearance
Key characters: 28 sympatric species but glaucous coating completely diagnostic
Habitat and range
Habitat: Well-drained, gravelly soils, streambanks, roadsides
Elevation: 150-3000 m
California counties: Riverside, Los Angeles, San Bernardino, Sierra, Lake, Nevada, Tulare, Tuolumne, Inyo, Plumas, Siskiyou, Trinity, Fresno, Calaveras, Kern, Shasta, Mono, Humboldt, Butte, El Dorado, Placer, Madera, Tehama, Mariposa, Amador, Alpine, Modoc, Lassen, Del Norte, Ventura, Glenn, San Diego, Mendocino
Outside California: to Washington, Idaho, Utah, northern Mexico
Bloom period
Epilobium glaberrimum subsp. glaberrimum blooms Jun-Sep.
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 glaberrimum subsp. glaberrimum native to California?
Yes. Epilobium glaberrimum subsp. glaberrimum is native to California (recorded as native).
When does Epilobium glaberrimum subsp. glaberrimum bloom?
Epilobium glaberrimum subsp. glaberrimum blooms Jun-Sep.
Where in California does Epilobium glaberrimum subsp. glaberrimum grow?
Epilobium glaberrimum subsp. glaberrimum occurs in Riverside, Los Angeles, San Bernardino, Sierra, Lake, Nevada, Tulare, Tuolumne and other counties, at elevations of 150-3000 m.
What plant family does Epilobium glaberrimum subsp. glaberrimum belong to?
Epilobium glaberrimum subsp. glaberrimum is in the Onagraceae family, genus Epilobium.
What habitat does Epilobium glaberrimum subsp. glaberrimum grow in?
Epilobium glaberrimum subsp. glaberrimum grows in Well-drained, gravelly soils, streambanks, roadsides.
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.