Cosmos bipinnatus
Garden cosmos
(c) Irving Merino, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Herb · Not Native
Cosmos bipinnatus (Garden cosmos) is a non-native California herb in the Asteraceae family, recognized by ray color and leaf segment width are clearly diagnostic.
Garden cosmos is a naturalized perennial found in southern California coastal regions and cultivated areas in the California Floristic Province at elevations below 1,000 meters in disturbed places. Flowering from April to August, this plant produces white to pink or purple ray flowers with distinctive daisy-like heads up to 15 millimeters wide. Growing with upright stems 10 to 200 centimeters tall, it has a glabrous or slightly puberulent appearance. Its finely divided leaves have intricate, linear segments less than 1.5 millimeters wide, creating a delicate, feathery foliage. The fruit is black and 7 to 16 millimeters long with occasional short pappus awns.
Identification and appearance
Key characters: 1 sympatric species; ray color and leaf segment width are clearly diagnostic
Habitat and range
Habitat: Uncommon escape from cultivation in disturbed places
Elevation: < 1000 m
Outside California: native to tropical America
Bloom period
Cosmos bipinnatus blooms Apr-Aug.
How to tell it apart
vs Eriocapitella: Eriocapitella has simple lobed leaves, not the thread-like dissected foliage of Cosmos.; vs Tagetes: Tagetes has strongly aromatic foliage when crushed; Cosmos lacks strong scent.; vs Eupatorium: Eupatorium has simple opposite leaves and dense clusters of small fuzzy flowers, not large showy rays.; vs Zinnia: Zinnia has simple, undivided leaves; Cosmos has finely dissected thread-like leaf segments.; vs Dahlia: Dahlia has compound leaves with broad leaflets; Cosmos has thread-like dissected segments.
Frequently asked questions
Is Cosmos bipinnatus native to California?
No. Cosmos bipinnatus is not native to California (recorded as not native).
When does Cosmos bipinnatus bloom?
Cosmos bipinnatus blooms Apr-Aug.
What plant family does Cosmos bipinnatus belong to?
Cosmos bipinnatus is in the Asteraceae family, genus Cosmos.
What habitat does Cosmos bipinnatus grow in?
Cosmos bipinnatus grows in Uncommon escape from cultivation in disturbed places.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.