Ranunculus bulbosus
Bulbous buttercup
(c) Douglas Goldman, some rights reserved (CC BY-SA), uploaded by Douglas Goldman · licence
Family: Ranunculaceae · Type: Herb · Not Native
Ranunculus bulbosus (Bulbous buttercup) is a non-native California herb in the Ranunculaceae family, recognized by bulbous stem base and reflexed sepals diagnostic.
Bulbous buttercup is a naturalized perennial herb found in northern California Coast bioregion in meadow habitats at elevations below 100 meters. Flowering from June to July, this plant produces yellow flowers with five petals 9 to 13 millimeters long, accompanied by reflexed sepals. Growing with an erect stem 20 to 30 centimeters tall, it features a distinctive bulbous base resembling a corm. Its basal and cauline leaves are deeply lobed, with ovate to cordate blades divided into 1 to 2 lobed leaflets, featuring ultimate segments that are oblong to obovate with rounded tips. The fruit is a disk-like body with a slender, hooked beak 2.2 to 3.2 millimeters wide.
Identification and appearance
Key characters: 22 sympatric species; bulbous stem base and reflexed sepals diagnostic
Habitat and range
Habitat: Meadows
Elevation: < 100 m
Outside California: worldwide, native to Eurasia
Bloom period
Ranunculus bulbosus blooms Jun-Jul.
How to tell it apart
vs Lasthenia: Ranunculus has separate petals around a central disk; Lasthenia has many tiny ray flowers around a disk (composite head).; vs Bowlesia: Ranunculus has glossy yellow petals in conspicuous flowers; Bowlesia has tiny white flowers in umbels with divided leaves.; vs Potentilla: Ranunculus has nectaries at petal bases and many pistils; Potentilla has no nectaries and styles attached to ovary sides.; vs Papaver: Ranunculus has 5 petals and many pistils; Papaver has 4 crinkled petals and a single large stigma disk.; vs Oxalis: Ranunculus has glossy separate petals; Oxalis has clover-like leaves and tubular flowers that close at night.
Frequently asked questions
Is Ranunculus bulbosus native to California?
No. Ranunculus bulbosus is not native to California (recorded as not native).
When does Ranunculus bulbosus bloom?
Ranunculus bulbosus blooms Jun-Jul.
What plant family does Ranunculus bulbosus belong to?
Ranunculus bulbosus is in the Ranunculaceae family, genus Ranunculus.
What habitat does Ranunculus bulbosus grow in?
Ranunculus bulbosus grows in Meadows.
Related species
Other California species in the same genus, family, or bioregion.
- Ranunculus californicus — California buttercup
- Ranunculus californicus var. californicus — Common buttercup
- Ranunculus californicus var. cuneatus — Common buttercup
- Ranunculus canus — Great valley buttercup
- Ranunculus canus var. canus — Hartweg's buttercup
- Ranunculus canus var. ludovicianus — Hartweg's buttercup
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.