Melilotus officinalis
Yellow sweetclover
(c) Patrick Hacker, some rights reserved (CC BY), uploaded by Patrick Hacker · licence
Family: Fabaceae · Type: Herb · Not Native
Melilotus officinalis (Yellow sweetclover) is a non-native California herb in the Fabaceae family, recognized by tall erect habit and long flower clusters diagnostic from sourclover.
Yellow sweetclover is a naturalized biennial found throughout California in open fields and disturbed sites at elevations below 2,300 meters. Flowering from May to August, this plant produces bright yellow flowers in slender, elongated clusters 3 to 8 centimeters long. Growing with sturdy stems 50 to 200 centimeters tall that range from nearly smooth to slightly hairy, it develops an upright, branching form. Its compound leaves have elliptic to obovate leaflets 10 to 25 millimeters long with slightly toothed edges. The small fruits are plump, 3 to 5 millimeters long with irregular cross-ridged surfaces.
Identification and appearance
Key characters: 2 sympatric species; tall erect habit and long flower clusters diagnostic from sourclover
Habitat and range
Habitat: Open fields, disturbed sites, cultivated
Elevation: < 2300 m
California counties: Alpine, San Bernardino, Los Angeles, San Diego, Inyo, Fresno, Riverside, Santa Barbara, San Francisco, Lake, Amador, Yolo, Modoc, Colusa, Plumas, Trinity, Butte, Sierra, Tehama, Glenn, Nevada, Lassen, Mono, Napa, Ventura, Mendocino, Humboldt, San Luis Obispo, Santa Clara, El Dorado, Sacramento, Kern, Monterey, Mariposa
Outside California: widely distributed in temperate areas, especially northern and central United States, native to Eurasia
Bloom period
Melilotus officinalis blooms May-Aug.
How to tell it apart
vs Medicago: Melilotus fruits are egg-shaped with ridges; Medicago fruits are spirally coiled.; vs Trifolium: Melilotus flowers fall off after blooming; Trifolium flowers persist and enclose fruits.; vs Oxalis: Melilotus has pea-shaped flowers in spikes; wood-sorrels (Oxalis) have 5-petaled flowers in umbels.; vs Acmispon: Melilotus has toothed leaflets and ridged oval fruits; Acmispon has smooth leaflets and elongate pods.; vs Baccharis: Melilotus has compound leaves and pea flowers; Baccharis has simple leaves and brush-like composite flower heads.
Frequently asked questions
Is Melilotus officinalis native to California?
No. Melilotus officinalis is not native to California (recorded as not native).
When does Melilotus officinalis bloom?
Melilotus officinalis blooms May-Aug.
Where in California does Melilotus officinalis grow?
Melilotus officinalis occurs in Alpine, San Bernardino, Los Angeles, San Diego, Inyo, Fresno, Riverside, Santa Barbara and other counties, at elevations of < 2300 m.
What plant family does Melilotus officinalis belong to?
Melilotus officinalis is in the Fabaceae family, genus Melilotus.
What habitat does Melilotus officinalis grow in?
Melilotus officinalis grows in Open fields, disturbed sites, cultivated.
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.