Data provided by the participants of the Consortium of California Herbaria

View additional distribution information on the Jepson eflora

Ceanothus arboreus is a species of shrub endemic to California, especially to the Channel Islands. It is known commonly as feltleaf ceanothus. It is a species of what are sometimes called California lilacs, and may be referred to as the California mountain lilac or island mountain lilac. It is one of the tallest of the genus, growing up to 25-30 ft. in height, bearing glossy dark green leaves which are leathery or felt-like on their undersides. It is sometimes planted as a fast-growing ornamental for its showy bright blue flowers, which grow in plentiful panicles, or bunches, of tiny five-lobed blossoms. Some varieties and cultivars have light, powder blue blooms, and others bear darker blue flowers. One named variety is known as 'Owlswood Blue'. The species is used as a parent in popular ornamental hybrids such as 'Ray Hartman'. The fruits are three-lobed, triangular capsules. As a native of dry California, the plant is drought-tolerant and may be found in chaparral ecosystems. It has a reputation for being short lived, but life span is improved by not overwatering, withholding summer water and replicating natural conditions as much as possible.

Plant type

Shrub

Size

20 - 30 ft Tall
10 ft Wide

Form

Rounded

Growth rate

Fast

Dormancy

Evergreen

Fragrance

Pleasant

Calscape icon
Color

Blue

Flowering season

Winter, Spring

Special uses

Bank stabilization

Sun

Full Sun

Water

Very Low

Summer irrigation

Never irrigate once established

Ease of care

Easy

Cold tolerance

Tolerates cold to 15° F

Soil drainage

Fast, Medium

Soil description

Tolerates a variety of soils but does best and lives longest in well drained soil.
Soil PH: 6.0 - 8.0

Maintenance

Prune in dry season to reduce chance of infection through the wound

Propagation

Because Ceanothus species hybridize freely, propagation by cuttings is usually recommended in order to obtain a true representative of a given taxa.  For propagating by seed: Hot water; then 2 mos. stratification may improve germination.

Sunset Zones

7, 8, 9, 14*, 15*, 16*, 17*, 19*, 20*, 21*, 22*, 23*, 24*

Site type

Dry slopes among chaparral, primarily on the Channel Islands. Does best near the coast (within about 20 miles) where island conditions can be replicated.

Plant communities

Chaparral

Bats
Birds
Bees
Caterpillars
Butterflies

Butterflies and moths supported

1 confirmed and 19 likely

Confirmed Likely

Orange Tortrix Moth

Argyrotaenia franciscana

Alfalfa Looper Moth

Autographa californica

Drepanulatrix hulstii