Coast Whitethorn

Ceanothus incanus

Coast Whitethorn

John Rusk from Berkeley, CA, United States of America

Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Rhamnaceae
Genus:
Ceanothus
Species:
Ceanothus incanus

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Shrub
Height:
12-20 ft
Light Requirements:
Full Sun
Drought Tolerance:
High
Bloom Months:
apr, may, jun
Bloom Colors:
White, Pink
Evergreen Shrub:
Yes
Landscaping Shrub:
Yes

Native Range

United States: California

Keystone Species Ranking

Caterpillar Keystone:
★★☆☆☆ Based on number of butterfly and moth species using this genus as host plant (Source: National Wildlife Federation)

Host Plant for Caterpillars

Western tent caterpillar (Malacosoma californica), California tortoiseshell (Nymphalis californica)

Soil Requirements

Soil Type:
sandy, well-drained, nutrient-poor soil
pH:
5.5 - 7.0 (slightly acidic to neutral)
Drainage:
excellent drainage required
Moisture:
dry to moderate
Notes:
prefers open, sunny habitats

Germination Information

Pre-treatment: Seeds are placed in fine mesh bags, soaked for 10 seconds in boiling water and then immediately transferred in cold water. Seeds are then placed into a 1% hydrogen peroxide (3:1 water/3% hydrogen peroxide) soak for 24 hours, rinsed, and placed in water for an additional 4 hours. Seeds are sown into trays filled with stabilized medium plugs (Q-plugs). Trays are sealed inside plastic bags and placed into refrigeration at 1 to 3 °C for 90 days. Trays are checked weekly and kept moist throughout the stratification period. If mold is evident, trays should be treated with 1% hydrogen peroxide.

Establishment: Ceanothus cordulatus, also known as whitethorn ceanothus or white ceanothus, is generally found in Oregon, California, Nevada and within mattoral vegetation association of California. There is a variation in the pre-planting propagule treatments across the protocols, with one suggesting that seeds germinate at greenhouse temperatures without any specific treatment.

Source: npn.rngr.net