Plants 0.3-4 dm, sparsely pilose to densely hirsute. Leaves mostly basal, 0.5-8.5 cm; blade linear; margins entire. Inflorescences: peduncle 2.5-38 cm; bud globose to ovoid-cylindric. Flowers: petals white to cream colored, sometimes with yellow tips, sometimes tinged red in age, narrowly ovate to obovate, 0.3-2 × 0.2-1 cm, apex acute to obtuse; ovary ovoid-ellipsoid; stigmas deltoid, margins revolute. Capsules ovoid, to 1.5 cm. Seeds dark, shining, smooth. 2 n = 14.
Flowering early-late spring. Open, grassy areas in grasslands, sand dunes, oak and pine woodlands; 0-1000 m; Calif.
Depauperate plants of this species may be confused with Meconella , but Hesperomecon can be distinguished by its linear, pilose leaves and ovoid capsules. Robust plants may be confused with Platystemon , but the strictly 3-carpellate, strongly syncarpous gynoecium and valvate capsules of Hesperomecon are always diagnostic.