Page authors: Don Knoke, David Giblin
Oenothera flava
long-tubed evening primrose

Distribution: Occurring east of the Cascades crest, where known historically from the south-central area. Washington to California, east to the Rocky Mountains and Great Plains.

Habitat: Hard-packed soil in swales or around vernal pools in the plains and lower foothills.

Flowers: July-August

Origin: Native

Growth Duration: Perennial

Conservation Status: Historical in Washington (WANHP)

Pollination: Bees, moths


Tufted, acaulescent, sub-glabrous perennial.


Leaves basal, in rosettes, oblanceolate, 5-20 cm. long and up to 15 mm. broad, the lower third pinnatifid with backward-angled lobes, the upper portion entire or wavy-dentate.


Flowers sessile; calyx tube purplish, slender, 2-12 cm. long, the 4 lobes reflexed, free or partly fused and turned to one side; petals 10-20 mm. long, yellow, aging to purplish; stamens 8; stigma with 4 linear lobes 3 mm. long; ovary inferior, 4-celled.


Capsule woody, ovoid, 10-20 cm. long, conspicuously winged.

Accepted Name:
Oenothera flava (A. Nelson) Garrett
Publication: Spring Fl. Wasatch (ed. 4) 106. 1927.

Synonyms & Misapplications:
Oenothera flava (A. Nelson) Garrett ssp. flava [JPM]
Additional Resources:

PNW Herbaria: Specimen records of Oenothera flava in the Consortium of Pacific Northwest Herbaria database

WA Flora Checklist: Oenothera flava checklist entry

OregonFlora: Oenothera flava information

E-Flora BC: Oenothera flava atlas page

CalPhotos: Oenothera flava photos

1 photographs:
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