Helianthus petiolaris

Prairie sunflower

Family: Asteraceae · Type: annual · Native

Prairie sunflower is a California native annual found in open grasslands and disturbed areas across western North American plains and valleys. Flowering from July to October, this plant produces bright yellow ray flowers surrounding a disk of red to purple flower centers, creating large sunflower heads 15 to 25 millimeters in diameter. Growing with erect stems 40 to 200 centimeters tall, covered in stiff gray or white hairs, the plant develops a distinctive branching structure. Its leaves are mostly alternate, with blades 4 to 15 centimeters long, lance-shaped to widely ovate, having wedge-shaped or slightly heart-shaped bases and entire or slightly toothed margins. The plant produces small fruits 3 to 4.5 millimeters long, characteristic of sunflower species.

Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Jepson eFlora, Cal-IPC, and more.