Rudbeckia glaucescens
Waxy cone-flower
(c) Ken-ichi Ueda, some rights reserved (CC BY) · licence
Family: Asteraceae · Type: Herb · Native
Rudbeckia glaucescens (Waxy cone-flower) is a native California herb in the Asteraceae family.
Waxy cone-flower is a California native perennial found in northern California Coast and Klamath Ranges in meadows, seeps, and streambanks, often on serpentine landscapes at elevations of 60 to 1,300 meters. Flowering from July to September, this plant produces yellow-green flowers with 7 to 15 ray flowers up to 4 centimeters long that are often reflexed, creating distinctive radiate flower heads. Growing with stout stems 50 to 150 centimeters tall that are glaucous and blue-green, it develops from a robust rhizome with a simple to sparingly branched structure. Its leaves are lanceolate to elliptic, 20 to 50 centimeters long and 3 to 10 centimeters wide, with smooth edges or occasionally few shallow teeth, presenting a glaucous blue-green appearance. The flower heads feature a prominent conic to columnar receptacle up to 3.5 centimeters long, with brown-tinged paleae and disk flowers in green-yellow tones.
Identification and appearance
Key characters: 2 sympatric species; key differentiators are glaucous foliage and presence of ray flowers
Habitat and range
Habitat: Meadows, seeps, mires, streambanks, often on serpentine
Elevation: 60-1300 m
California counties: Del Norte, Siskiyou, Trinity
Outside California: southwestern Oregon
Bloom period
Rudbeckia glaucescens blooms Jul-Sep.
How to tell it apart
vs Encelia: Rudbeckia has a tall dark cone center; Encelia has tiny or absent ray petals and flat centers.; vs Helianthus: Rudbeckia has a tall dark cone-shaped center; Helianthus has a flat or gently rounded yellow center.; vs Helenium: Rudbeckia has a cone that starts flat-topped; Helenium has a round ball-shaped center from the start.; vs Ratibida: Rudbeckia fruits are smooth-edged; Ratibida fruits have hairy fringed edges.; vs Gazania: Rudbeckia has a tall cone center; Gazania has a flat center with distinctive dark markings at petal bases.
Frequently asked questions
Is Rudbeckia glaucescens native to California?
Yes. Rudbeckia glaucescens is native to California (recorded as native).
When does Rudbeckia glaucescens bloom?
Rudbeckia glaucescens blooms Jul-Sep.
Where in California does Rudbeckia glaucescens grow?
Rudbeckia glaucescens occurs in Del Norte, Siskiyou, Trinity, at elevations of 60-1300 m.
What plant family does Rudbeckia glaucescens belong to?
Rudbeckia glaucescens is in the Asteraceae family, genus Rudbeckia.
What habitat does Rudbeckia glaucescens grow in?
Rudbeckia glaucescens grows in Meadows, seeps, mires, streambanks, often on serpentine.
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.