San Diego Natural History Museum--Your Nature Connection[BRCC San Diego Natural History Museum: Research Library]
Plants that Attract Butterflies, A Gallery of Paintings by Albert Valentien

Painting of Ceanothus tomentosus, by Albert Valentien

Ceanothus tomentosus (Wooly ceanothus)
Painted by Albert Valentien
© San Diego Natural History Museum

Ceanothus tomentosus

Wooly Ceanothus is an evergreen shrub, often with grayish-green bark, growing to 18 feet, with beautiful panicles of azure-blue to nearly white flowers. The name "tomentosus" refers to the fuzzy underside of the leaf. A member of the Rhamnaceae or buckthorn family, it is one of about 40 species of the genus Ceanothus that grow in our region. Because these shrubs are common in chaparral on hillsides and mountains throughout southern California and Baja Calfornia, the flowers can look like a purple mist over the hills in San Diego's backcountry.

Although some people refer to Ceanothus as California lilac, it is not even in the same family as the lilac of eastern and midwestern United States. A drought-resistant plant well-adapted to its environment, Ceanothus often regrows readily after chaparral fires, either by stump-sprouting from underground portions, or by seeds that germinate after being burned.

Tiger Swallowtail butterflies use species of Ceanothus as host plants. This plant also serves as an important browse for deer, and was used by the indigenous peoples of southern California to make a treatment for poison oak and other skin irritants.

Introduction to Valentien Collection
Gallery of Plants
Monarca: A Gallery of Butterfly Plants

Text by Margaret Dykens