Oenothera californica is a perennial herb producing a spreading or upright stem up to 80 centimetres (31 in) long.

Flowers occur in the upper leaf axils, drooping in bud and becoming erect as they bloom.

The main threat to the Eureka Dunes evening primrose was off-road vehicle use.

That threat has been reduced and the plant's population has improved, but is still threatened by other human activities and an invasive species of tumbleweed, Prickly Russian thistle (Kali tragus).

The United States Fish and Wildlife Service had recommended the plant be removed from the endangered species list.