Ceanothus arboreus

Island Ceanothus

Plant Type: Tree
Sun: Partial Shade, Sun
Drainage: Medium, Well-draining
Water: Naturalize, Occasional
Height X Width: 25' X 10'
Santa Clara County Local: No
What do these mean?



The Island ceanothus is native to Santa Catalina, Santa Rosa and Santa Cruz Islands. It is the only ceanothus that I know of that naturally takes on a vase shape. Eventually, island ceanothus will become a single or multi-trunk tree. The glossy leaves (gray beneath) are also exceptional for their large size. The bark is silver and the late winter flowers are sky blue. Although this unusual lilac may be trained into a single-trunk tree, it naturally “wants” to be quite dense and leafy through many years of growth. Island ceanothus prefers a coastal setting and is reported to suffer in interior locations. My specimen has thrived for many years in full sun in Santa Clara County. More shade is certainly recommended if it is planted outside of climate zones 15, 16 or 17 in Northern California. Blooms in late February in Santa Clara County.


Deer Resistant: Somewhat
Attractive to Bees: Yes
Attractive to Butterflies: Yes
Good Under Oaks: No
Evergreen or Deciduous: Evergreen