Rhododendron occidentale
California azalea, California Azalea
(c) Brian Finzel, some rights reserved (CC BY-SA) · licence
Family: Ericaceae · Type: Shrub · Native
Rhododendron occidentale (California azalea) is a native California shrub in the Ericaceae family, recognized by deciduous leaves and 5 stamens vs evergreen leaves and 10 stamens.
California azalea is a native shrub found in northwestern California, the Cascade Range, northern Sierra Nevada, Sierra Nevada, Great Valley, Central Coast, San Francisco Bay Area, northern Santa Cruz Mountains, and Peninsular Ranges in streambanks, ocean bluffs, moist wooded slopes, canyon bottoms, and serpentine ridges at elevations up to 2,700 meters. Flowering from April to August, this shrub produces white to pink to salmon-colored flowers with yellow or orange blotches on the upper petal, arranged in compact clusters of 3 to 15 blooms. Growing up to 8 meters tall with densely branched stems covered in sparse to dense hairs, it forms a multi-stemmed, spreading structure. Its deciduous leaves are 3.5 to 8.2 centimeters long with ciliate margins, creating a delicate green backdrop for the showy flowers. The fruit develops longer than wide, splitting open from tip to base and containing ovate to fusiform seeds.
Identification and appearance
Key characters: 2 sympatric species; key features are deciduous leaves and 5 stamens vs evergreen leaves and 10 stamens
Habitat and range
Habitat: Streambanks, ocean bluffs, moist wooded slopes and canyon bottoms, serpentine ridges
Elevation: < 2700 m
California counties: Mendocino, San Diego, Riverside, Placer, Lake, Del Norte, Napa, Tuolumne, Madera, Sonoma, Nevada, Siskiyou, Tulare, San Bernardino, Santa Cruz, Plumas, Humboldt, Sierra, Fresno, El Dorado, San Mateo, Santa Clara, Butte, Calaveras, Marin, Monterey, Yuba, Colusa, Trinity, Shasta, Tehama, San Benito, San Francisco, Mariposa, Kern, Amador, Solano, Mono
Outside California: Oregon
Bloom period
Rhododendron occidentale blooms Apr-Aug.
How to tell it apart
vs Rosa: Rhododendron has tubular bell-shaped flowers; Rosa has flat open flowers with separate petals.; vs Nerium: Rhododendron has alternate leaves; Nerium has leaves in whorls of 3-4.; vs Cordia: Rhododendron has fused petals forming tubes; Cordia has separate spreading petals.; vs Hibiscus: Rhododendron has many separate stamens; Hibiscus has stamens fused into a central column.; vs Gardenia: Rhododendron has alternate leaves; Gardenia has opposite or whorled leaves.
Frequently asked questions
Is Rhododendron occidentale native to California?
Yes. Rhododendron occidentale is native to California (recorded as native).
When does Rhododendron occidentale bloom?
Rhododendron occidentale blooms Apr-Aug.
Where in California does Rhododendron occidentale grow?
Rhododendron occidentale occurs in Mendocino, San Diego, Riverside, Placer, Lake, Del Norte, Napa, Tuolumne and other counties, at elevations of < 2700 m.
What plant family does Rhododendron occidentale belong to?
Rhododendron occidentale is in the Ericaceae family, genus Rhododendron.
What habitat does Rhododendron occidentale grow in?
Rhododendron occidentale grows in Streambanks, ocean bluffs, moist wooded slopes and canyon bottoms, serpentine ridges.
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.