Ceanothus otayensis
Otay mountain ceanothus, Otay Mountain Ceanothus
Photo by Chez Brungraber
Family: Rhamnaceae · Type: Shrub · Native
Conservation status: CNPS 1B.2
Ceanothus otayensis (Otay mountain ceanothus) is a native California shrub in the Rhamnaceae family, recognized by opposite leaves toothed only in distal third distinctive.
Otay mountain ceanothus is a rare (CNPS 1B.2) California native shrub found in southern Peninsular Ranges and southern Southern Coast Ranges, specifically on Otay Mountain, San Miguel Mountain, and Miramar in rocky chaparral slopes at elevations of 120 to 1,100 meters. Flowering from January to April, this plant produces pale blue flowers in compact umbel-like clusters 0.5 to 2 centimeters long. Growing as an erect, open shrub less than 2 meters tall with ascending gray-brown twigs, it features distinctively structured leaves. Its opposite, evergreen leaves are obovate to oblong-obovate, 5 to 12 millimeters long, with a dull green upper surface and paler lower surface, featuring small teeth in the distal third and a truncate to notched tip. The compact shrub has thick, rolled leaf margins and develops small fruits approximately 4 to 6 millimeters wide.
Identification and appearance
Key characters: 24 sympatric species; opposite leaves toothed only in distal third distinctive
Habitat and range
Habitat: Rocky slopes, chaparral
Elevation: 120-1100 m
Outside California: northern Baja California
Bloom period
Ceanothus otayensis blooms Jan-Apr.
Conservation status
CNPS 1B.2
How to tell it apart
vs Rhamnus: Ceanothus has showy blue/white/pink flowers in dense clusters; Rhamnus has tiny inconspicuous greenish flowers.; vs Quercus: Ceanothus has showy flower clusters and small leaves; Quercus has acorns and distinctive lobed or toothed oak leaves.; vs Baccharis: Ceanothus has individual flowers with 5 separate petals; Baccharis has composite flower heads with tiny disc flowers.; vs Cercocarpus: Ceanothus has blue/white/pink flowers in clusters; Cercocarpus has tiny flowers with no petals and feathery fruiting tails.; vs Adenostoma: Ceanothus flowers have 5 distinct colored petals; Adenostoma has tiny white flowers and needle-like clustered leaves.
Frequently asked questions
Is Ceanothus otayensis native to California?
Yes. Ceanothus otayensis is native to California (recorded as native).
When does Ceanothus otayensis bloom?
Ceanothus otayensis blooms Jan-Apr.
What plant family does Ceanothus otayensis belong to?
Ceanothus otayensis is in the Rhamnaceae family, genus Ceanothus.
Is Ceanothus otayensis rare or endangered?
Ceanothus otayensis carries California Rare Plant Rank 1B.2, state rank S1.
What habitat does Ceanothus otayensis grow in?
Ceanothus otayensis grows in Rocky slopes, chaparral.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos · CDFW CNDDB
Last updated 2026-09-30
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.