Asteraceae Ratibida pinnata
Family Name
Asteraceae
Description
Ratibida pinnata is a perennial herb with 30-120 cm, simple, hairy stems arising singly or in clusters from a rhizome. The stems can become branched in the region the inflorescence develops. The simple, alternate, petiolate leaves are up to 40 cm long and deeply pinnately divided, with the larger segments pointed and lance-ovate in shape. The margins vary from coarsely toothed to entire and the leaf surfaces are covered with short stiff hairs. The leaves are reduced in size as they ascend the stem becoming bract-like near the top. There are 1 to 12 flower heads at the top of the plant, each at the end of a long peduncle, and having a globular to oblong receptacle 1-2.5 cm tall and 1-2 cm wide, surrounded by 10-14 involucral bracts in 2 series. The heads have up to 15 yellow ray flowers, the ligules 3-6 cm long, spreading to drooping. The numerous greenish purple to brown disk flower’s corollas are 1.3-3 mm long and lack a pappus. The achenes are 2-3 mm in length. Gray-headed coneflower blooms from June through September in prairies and open woodlands on the eastern edge of South Dakota.
Horticulture Notes
Seed Collection: Collect seed in mid to late summer
Germination: Seeds are somewhat dormant. Treatment with a 1 mM Ethephon solution for 2 weeks or 30-day cold treatment will allow spring sowing. Fall sowing is also an easy option.
Soils: Tolerates most soil types, but prefers well-drained, usually calcareous soils. Light: Full sun
Water: Prefers moist conditions but can withstand dryer conditions.
Additional Notes
Gray-headed Coneflower is similar to the more common R. columnifera in appearance but is a bit more robust, also making a colorful addition to any native plant garden. They attract many different native bees and butterflies, and their seeds are eaten by several species of songbirds.