Taller individuals are more common. It seems to me that the shortest individuals tend to grow in the dryest areas. I plan to transplant some of them to irrigated places next Spring to see if they grow taller. R. californica spreads by suckering, eventually forming large thickets. The stems are straight and very spiney.
Leaves are medium to dark matte green and typically have seven leaflets.
R. californica seems immune to mildew and rust. It does get a little blackspot when stressed, but doesn't seem to lose any leaves to it. The fragrant flowers open from long pointed buds. Flower color varies from cool medium pink to white. Flowers are produced in clusters of various sizes.