Some species grow in the eastern U.S., Rocky Mountains, the Northwest, and Mexico, but most are native to California. In flower color, they range from white through all shades of blue, from pale powder blue to deep violet-blue. Typically flower in spring. Plants vary greatly in habit: some are low and spreading, others compact and bushy, still others upright and angular. Generally evergreen; a couple listed here lose leaves in cold weather. Only types with small leaves tend to be deer-resistant.
New varieties (most of them propagated from selected wild plants) appear frequently in nurseries, while old ones disappear. For the widest choice, deal with a specialist in Western natives. In Zones 1–3, 8, 9, stay with varieties tested and sold locally.
In the wild, these plants grow on rocky slopes; in the garden, they require excellent drainage. Plant in light, well-drained soil. Some demand total dryness during summer, but others (particularly coastal groundcover types) need occasional summer water if grown away from the fog belt. A few tolerate more frequent summer moisture.
Wait until after blooms have faded to do any pruning, and avoid cutting off any branches more than an inch in diameter. Control plant growth by pinching back shoot tips during the growing season. Ceanothus sometimes get aphids and whiteflies, but these are easy to control.Ceanothus thyrsiflorus
Glossy green leaves to 2 in. Light to dark blue, 3-in. spikelike clusters. One of the largest (to 20 ft. tall, 30 ft. wide) and hardiest ceanothus. Does well with only occasional deep irrigation in summer.‘Skylark’
From 3–6 ft. tall, 5 ft. wide. Glossy, medium green, 2-in. leaves. Dark blue flower clusters; profuse bloom over a long season. Tolerates summer water.‘Snow Flurry’
From 6–10 ft. tall, 8–12 ft. wide. Rich green 2-in. leaves. Profuse pure white flower clusters. Adaptable, dependable. Good choice for coastal gardens.
Has been confused with C. t. ‘Skylark’ but seems to be a larger plant, to 9 ft. tall and 12 ft. wide. Profuse show of deep violet-blue blooms over a long season.
Spiky clumps of narrow, lime green leaves grow 8–18 in. tall and wide. Attractive light tan flow...
‘William Hertrich’ has very large, semidouble, deep red flowers with heavy petals.
With the look of a giant artichoke—they’re related—this Mediterranean native (Cy...