This California lilac is an evergreen 5' shrub to small tree. (This form is more of a four foot mound.) Flowers May-June with a good light blue show. They are not very cold hardy. They usually grow back at 15 degrees F. But they look as if they have been hit with a blowtorch. It's fast and attractive along the coasts and in the San Joaquin Valley . It's planted in full sun at CALM in Bakersfield and looks great. Away from the coast it needs a little extra water at the drip line to survive. Once a month is ok, will do ok at 1/week as long as the crown stays dry. Can be one of the most attractive plants in your garden if the temperatures at your site do not go below 15 degrees F. It grows on old ocean beaches and bluffs near Arroyo de la Cruz Creek north of San Simeon, (north to the central portion of the north coast of California). The soil varies from a near adobe through red clay on hard pan to a gray sand-rock composite. It receives summer fog and rainfall of about 20-30 inches per year. It is one of the most moderate climates in the world. Every day has a high of 60-65 degrees F. and a low of 50 degrees F. Some of its associated plants in the coastal sage scrub/coastal chaparral, and remnant closed-cone pine forest plant communities are Ceanothus hearstiorum, Rhamnus californica, Heteromeles arbutifolia, Adenostoma fasciculatum, Iris douglasii, Lonicera involucrata, some Pinus radiata, Baccharis pilularis, Salvia mellifera, Toxicodendron diversilobum, Diplacus aurantiacus, and Lupinus arboreus (among others). In some places it grows to within 50 ft. (20 meters) of the coastal bluff.
Ceanothus thyrsiflorus 'Big Sur ' tolerates seaside conditions and clay.
Foliage of Ceanothus thyrsiflorus 'Big Sur ' has color silver and is evergreen.
Flower of Ceanothus thyrsiflorus 'Big Sur ' has color blue.
Communities for Ceanothus thyrsiflorus 'Big Sur ':Chaparral, Mixed-evergreen Forest, Northern Coastal Sage Scrub and Redwood Forest.