It is only known from a few sites in the vicinity of Vail Lake and the Black Hills, east of Temecula and west of the Santa Rosa Mountains in southwestern Riverside County.

[1] Ceanothus ophiochilus is a plant of the chaparral plant community, and in its small native range which currently is only a few acres, it grows in pyroxenite soil atop an ancient volcano.

[1] One of the three remaining populations of this plant is on private property that may face development in the future.

[2] Ceanothus ophiochilus is an erect shrub reaching a maximum of 2 metres (6.6 ft) but generally shorter.

This species grows only from seed, unlike other Ceanothus, which via an evolved fire ecology usually crown sprout from the lignotuber root crown after being reduced aboveground, such as by natural wildfires.