Castilleja exserta, Purple Owl's Clover
Carpets of pink and purple in serpentine and other areas are created by the free-flowering habits of this low-growing, sun-loving annual with showy markings. It grows in early and mid-spring, often found in pools within masses of tidy tips and goldfields. It is a larval food plant for Bay Checkerspot butterfly.
It has very fine seed, so a little goes a long way. One packet will cover an area 2'x2', or 4 sq. ft. It tends to get swamped out when included in a wildflower mix with much taller species, so we suggest sowing it separately in pools within the planting.