Diodia sp.
Buttonweed, Buttonweed
Family: Rubiaceae · Type: Annual · Variable; species dependent
Diodia sp. (Buttonweed) is a non-native California annual in the Rubiaceae family.
How to tell it apart
vs Kelloggia: Diodia has stalkless flowers at leaf joints; Kelloggia has long-stalked flowers in open terminal clusters.; vs Crucianella: Diodia has opposite leaves and flowers at nodes; Crucianella has whorled leaves and dense terminal spikes.; vs Sherardia: Diodia has opposite leaves and desert habitat; Sherardia has whorled leaves and disturbed non-desert sites.; vs Galium: Diodia has opposite leaves and stalkless flowers; Galium has whorled leaves and stalked flowers in clusters.; vs Coprosma: Diodia is herbaceous with tiny flowers at nodes; Coprosma is a woody shrub with separate male-female plants.
Frequently asked questions
Is Diodia sp. native to California?
No. Diodia sp. is not native to California (recorded as variable; species dependent).
What plant family does Diodia sp. belong to?
Diodia sp. is in the Rubiaceae family, genus Diodia.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-04-14
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.