Stephanomeria diegensis
San diego milk aster
Photo by Chez Brungraber
Family: Asteraceae · Type: Herb · Native
Stephanomeria diegensis (San diego milk aster) is a native California herb in the Asteraceae family, recognized by very tall stature, glandular-puberulent stems, and reflexed phyllaries.
San diego milk aster is a California native annual found in southern California coastal regions, Channel Islands, western Transverse Ranges, and Peninsular Ranges in old clearings, sand dunes, and chaparral openings at elevations of 20 to 600 meters. Flowering from July to January, this delicate plant produces pale pink to white flowers in small clusters along slender branches. Growing 50 to 200 centimeters tall with ascending or spreading branches, it has a glandular-puberulent stem with reduced bract-like cauline leaves. Its basal leaves typically wither by flowering time, creating a sparse, open growth structure. The fruit develops with smooth faces and white plumose pappus bristles that are delicate and easily dispersed by wind.
Identification and appearance
Key characters: 9 sympatric species; distinguished by very tall stature, glandular-puberulent stems, and reflexed phyllaries
Habitat and range
Habitat: Old clearings, sand dunes, chaparral openings, roadside embankments
Elevation: 20-600 m
Outside California: northern Baja California
Bloom period
Stephanomeria diegensis blooms Jul-Jan.
How to tell it apart
vs Cichorium: Stephanomeria has pink-lavender flowers; chicory has bright blue flowers that close by noon; vs Malacothrix: Stephanomeria has pink-lavender flowers; Malacothrix has yellow or white flowers; vs Epilobium: Stephanomeria has dandelion-like composite flowers; Epilobium has 4-petaled simple flowers; vs Lactuca: Stephanomeria has small pink heads on wiry stems; Lactuca has yellow/blue flowers on leafy stems; vs Rafinesquia: Stephanomeria has pink-lavender flowers; Rafinesquia has white or cream flowers
Frequently asked questions
Is Stephanomeria diegensis native to California?
Yes. Stephanomeria diegensis is native to California (recorded as native).
When does Stephanomeria diegensis bloom?
Stephanomeria diegensis blooms Jul-Jan.
What plant family does Stephanomeria diegensis belong to?
Stephanomeria diegensis is in the Asteraceae family, genus Stephanomeria.
What habitat does Stephanomeria diegensis grow in?
Stephanomeria diegensis grows in Old clearings, sand dunes, chaparral openings, roadside embankments.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.