Calystegia purpurata subsp. saxicola
Coastal bluff morning-glory, Coastal Bluff Morning-Glory
(c) Garth Harwood, some rights reserved (CC BY) · licence
Family: Convolvulaceae · Type: Vine · Native
Conservation status: CNPS 1B.2
Calystegia purpurata subsp. saxicola (Coastal bluff morning-glory) is a native California vine in the Convolvulaceae family, recognized by weak climbing, closed leaf sinuses, wavy margins, leaf-like bracts.
Coastal bluff morning-glory is a rare (CNPS 1B.2) California native perennial found in central and northern California coastal regions including Brooks Island in Contra Costa County and San Francisco Bay Area, inhabiting rocky coastal scrub at elevations below 100 meters. Flowering from May to June, this plant produces lavender to purple flowers with distinctive trumpet-shaped blooms. Growing with trailing to weakly climbing stems generally less than one meter long, it spreads across rocky coastal terrain with a delicate, sprawling habit. Its leaves are uniquely shaped with ovate-triangular to kidney-like forms, featuring rounded lobes, slightly wavy margins, and tips that are generally rounded or softly notched. The plant's sinuous stems and gently curved leaves make it a characteristic element of California's coastal bluff ecosystems.
Identification and appearance
Key characters: 19 sympatric species; key features are weak climbing, closed leaf sinuses, wavy margins, leaf-like bracts
Habitat and range
Habitat: Rocky coastal scrub
Elevation: < 100 m
California counties: Mendocino, Sonoma, Marin
Bloom period
Calystegia purpurata subsp. saxicola blooms May-Jun.
Conservation status
CNPS 1B.2
How to tell it apart
vs Convolvulus: Convolvulus has smaller flowers with sharply pointed stigma lobes; Calystegia stigma lobes are blunt.; vs Ipomoea: Ipomoea stigma is a single rounded knob; Calystegia stigma has two distinct flattened lobes.; vs Datura: Datura flowers are upright with pleated edges; Calystegia flowers are smooth funnels.; vs Abronia: Abronia has clusters of small tubular flowers; Calystegia has single large funnel flowers.; vs Oenothera: Oenothera has four separate petals; Calystegia petals are fused into continuous funnel.
Frequently asked questions
Is Calystegia purpurata subsp. saxicola native to California?
Yes. Calystegia purpurata subsp. saxicola is native to California (recorded as native).
When does Calystegia purpurata subsp. saxicola bloom?
Calystegia purpurata subsp. saxicola blooms May-Jun.
Where in California does Calystegia purpurata subsp. saxicola grow?
Calystegia purpurata subsp. saxicola occurs in Mendocino, Sonoma, Marin, at elevations of < 100 m.
What plant family does Calystegia purpurata subsp. saxicola belong to?
Calystegia purpurata subsp. saxicola is in the Convolvulaceae family, genus Calystegia.
Is Calystegia purpurata subsp. saxicola rare or endangered?
Calystegia purpurata subsp. saxicola carries California Rare Plant Rank 1B.2, state rank S2S3.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
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.