Island Ceanothus, Ceanothus arboreus

About Island Ceanothus (Ceanothus arboreus) 23 Nurseries Carry This Plant

Add to My Plant List

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 Description

Plant Type

Shrub

Size

20 - 30 ft tall
10 ft wide

Form

Rounded

Growth Rate

Fast

Dormancy

Evergreen

Fragrance

Fragrant - Pleasant

Flower Color

Blue

Flowering Season

Winter, Spring

Wildlife Supported

Insects, especially bees, are attracted to the flowers. Birds such as quail and towhees are attracted to the seeds. Plants in the Ceanothus genus are host plants to the Spring Azure, Echo Blue, Pacuvius Duskywing, California Tortoiseshell, Pale Swallowtail, and Hedgerow Hairstreak butterflies.
Bird gardens

Butterflies & moths hosted ( 1 confirmed

, 20 likely * ) SHOW ALL

Western Avocado Leafroller Moth Amorbia cuneanaAmorbia cuneana

Gray Hairstreak Strymon melinusStrymon melinus

Pale Tiger Swallowtail Papilio eurymedonPapilio eurymedon

Hedgerow Hairstreak Satyrium saepiumSatyrium saepium

White-lined Sphinx Hyles lineataHyles lineata

Ceanothus Silkmoth Hyalophora euryalusHyalophora euryalus

Alfalfa Looper Moth Autographa californicaAutographa californica

Landscaping Information

Sun

Full Sun

Moisture

Very Low

Summer Irrigation

Never irrigate once established

Nurseries

Carried by 23

Ease of Care

Very 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

Common uses

Bank Stabilization, Bird Gardens, Butterfly Gardens, Bee Gardens

Companion Plants

Ideal companions are other island plants such as Catalina Cherry (Prunus ilicifolia ssp. lyonii), Island Mallow (Malva assurgentiflora), Island Live Oak (Quercus tomentella), and Island Ironwood (Lyonothamnus floribundus ssp. aspleniifolius), but any chaparral plants will also work.

Maintenance

Ceanothus are susceptible to aphids, white fly and a stem gall.. 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*

Natural Setting

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.

Climate

Annual Precipitation: 12.1" - 19.2", Summer Precipitation: 0.14" - 0.32", Coldest Month: 46.3" - 57.1", Hottest Month: 63.0" - 72.9", Humidity: 1.34" - 16.94", Elevation: 4" - 2066"

Alternative Names

Botanical Names: Ceanothus arboreus var. glabra
Common Names: Catalina Ceanothus, Feltleaf Ceanothus

Print Plant Sign Print Plant Label

Sources include: Wikipedia. All text shown in the "About" section of these pages is available under the Creative Commons Attribution-ShareAlike License. Plant observation data provided by the participants of the California Consortia of Herbaria, Sunset information provided by Jepson Flora Project. Propogation from seed information provided by the Santa Barbara Botanical Garden from "Seed Propagation of Native California Plants" by Dara E. Emery. Sources of plant photos include CalPhotos, Wikimedia Commons, and independent plant photographers who have agreed to share their images with Calscape. Other general sources of information include Calflora, CNPS Manual of Vegetation Online, Jepson Flora Project, Las Pilitas, Theodore Payne, Tree of Life, The Xerces Society, and information provided by CNPS volunteer editors, with special thanks to Don Rideout. Climate data used in creation of plant range maps is from PRISM Climate Group, Oregon State University, using 30 year (1981-2010) annual "normals" at an 800 meter spatial resolution.

Links: Jepson eFlora Taxon Page CalPhotos Wikipedia Calflora

Island Ceanothus

Ceanothus arboreus

Sign in to your Calscape Account X

Island CeanothusCeanothus arboreus

Sign in to your Calscape Account X

Island Ceanothus

Ceanothus arboreus