California Buckthorn
Frangula californica
- Native to:
- Mexico, United States
iNaturalist: © ekoberle (iNaturalist #174060453)






Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Rhamnaceae
- Genus:
- Frangula
- Species:
- Frangula californica
- USDA Symbol:
- FRCA12
Growth Characteristics
- Life Cycle:
- Perennial
- Growth Habit:
- Shrub , Tree
- Height:
- 450 cm
- Light Requirements:
- Full Sun
- Drought Tolerance:
- High
- Bloom Months:
- mar,apr,may,jun,jul
- Bloom Colors:
- green, yellow
- Landscaping Shrub:
- Yes
Wildlife Benefits
- Bees:
- ★☆☆☆☆ Documented bee visitation (GBIF)
- Butterflies & Moths:
- ★☆☆☆☆ Documented Lepidoptera association (GBIF)
- Caterpillars:
- ★★★☆☆ Recorded caterpillar host plant (HOSTS Database)
Host Plant for Caterpillars
Reported Fauna Sightings
Garden & Ecology Notes
- Wildlife Value:
- birds, butterflies, bees
- Deer Resistant:
- Yes
- Fire Ecology:
- Fire adapted — tolerates or benefits from fire
- Fire Notes:
- Resprouts vigorously from the root crown following fire; common in chaparral and coastal scrub fire regimes.
Soil Requirements
- Soil Type:
- well-drained, rocky or sandy soil
- pH:
- 5.5 - 7.5 (slightly acidic to neutral)
- Drainage:
- excellent drainage required
- Moisture:
- dry to moderate
- Notes:
- adapted to chaparral and woodland habitats
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 60–90 days
- Germination Time:
- 14–60 days
- Notes:
- Fresh seed germinates best; cold stratification improves germination rates for stored seed.
The above propagation data sourced from Claude AI
Pre-treatment: For seeds: Soak in fresh water for 24 hours, then place in a plastic ziplock bag with an equal amount of barely moistened perlite. Stratify for 2 to 3 months in a refrigerator, checking every 2 weeks for moisture content and mold development. For cuttings: Dip in a mild bleach solution for 30 seconds, make a 45 degree angle cut just below last node at the base of the cutting, leaving one leaf above the top node. Treat with Hormex (3000 ppm IBA) rooting powder.
Establishment: Seeds are collected between July 1st and October 1st, while hardwood cuttings are collected between November 1st and January 31st. F. californica is found in sandy and rocky places along the coast, below 3,500 feet elevation; from southern Oregon to Orange County, California.
Source: npn.rngr.net