This selection has proven somewhat problematic and short-lived in some mass plantings in the Santa Barbara area for reasons that are not clear. We recommend planting in well-drained soils rather than heavy or alkaline soils. In central and southern California gardens, plants will need occasional supplemental irrigation, especially when planted away from the coast. Hardy to 15° F.

We originally grew this cultivar under the name 'Darkest Blue'. 'Centennial' was officially named and introduced in 1992 and was selected from seed collected along the Sonoma County coast by Roger Raiche, horticulturist at UC Botanical Garden in Berkeley at the time. The garden was at that time celebrating its centennial anniversary, having been officially established in 1890 by E. L. Greene, the first chairman of the Department of Botany, to form a living collection of the native trees, shrubs, and herbaceous plants of the State of California, with the intent to further gather as rapidly as possible those of the neighboring states of the Pacific Coast.

The genus name comes from the Greek word keanthos which was used to describe a type of thistle and meaning a "thorny plant" or "spiny plant" and first used by Linnaeus in 1753 to describe New Jersey Tea, Ceanothus americanus. 

This information about Ceanothus 'Centennial' displayed is based on research conducted in our horticultural library and from reliable online resources. We also will relate observations made about it as it grows in our nursery gardens and other gardens we have visited, as well how the crops have performed in containers in our nursery field. We will also incorporate comments that we receive from others and we welcome hearing from anyone with additional information, particularly if they can share any cultural information that would aid others in growing it.