It is endemic to California, where it is known from the forests of the southernmost Cascade Range and northern Sierra Nevada.

It is an erect annual herb often exceeding half a meter in height.

As the bud opens the sepals all separate instead of remaining fused as those of many other Clarkia species do.

The triangular to semicircular petals are about 2 centimeters long and lavender to bright reddish-purple, sometimes with dark speckling.

There are 8 stamens with anthers all alike, and a protruding stigma.