Ceanothus arboreus x Owlswood Blue is evergreen shrub fast to 10 ft. Owlswwod Blue has blue flowers on long spikes and dark green shiny leaves. In coastal gardens plant in full sun and the plants will be fully drought tolerant in a year or so. Inland the plants will need some winter water. They'll tolerate clay but prefer good drainage. (Dig a shovel hole and full with water, if it takes longer than a day to drain it may not work.)
My thoughts about Ceanothus Owlswood Blue have mellowed. We had trouble with it as the deer like it, the bark burns in fulls sun and it's not super drought tolerant (by our standards). In a conventional garden there are no deer, it would be fully drought tolerant, garden tolerant, it's fast, clean looking and has a fair blue flower. Cold tolerant to 12- 15 f.
Ceanothus Owlswood Blue makes a nice screen or small tree. Grown by Malcolm Smith in his Larkspur Garden in the late 1940's. The seed source was a Ceanothus out of an Oakland garden. In test plantings at Saratoga Hort. the plants grew to 4 ft. tall and 9 ft. wide, in a garden in Nipomo they grew to 5 ft. tall and 6 ft. wide, in our interior heat they've grown to 10 ft. tall and 6 ft. wide. In the original Larkspur garden the plant grew to 15 ft. tall after 25 years and resembled Ceanothus arboreus. Click here for more about Mountain Lilacs.
Ceanothus arboreus 'Owlswood Blue' tolerates clay.
Foliage of Ceanothus arboreus 'Owlswood Blue' has color green and is evergreen.
Flower of Ceanothus arboreus 'Owlswood Blue' has color blue and has a fragrance.
Communities for Ceanothus arboreus 'Owlswood Blue':Coastal Sage Scrub.