General Culture:
This is an annual, biennial or short-lived perennial that will bloom in the first year from seed planted in spring. It is considered by many gardeners to perform best when grown as an annual. It grows well in average, medium moisture, well-drained soils in full sun. Best results occur in moist, organically rich loams. Tolerates hot and humid summers. Tolerates some drought once established. Appreciates good air circulation. Deadhead spent flowers to encourage additional bloom. For best results from seed in the St. Louis area, start seed indoors in late February to early March. Seed may also be planted directly in the garden after last spring frost date, however it may take up to 15 weeks before flowering commences. Purchasing plants in cell packs from nurseries in spring is another option. Whether or not plants survive from one year to the next, they freely self-seed in optimum conditions and will usually remain in the garden through self-seeding.
Noteworthy Characteristics:
‘Prairie Sun’ is a black-eyed Susan (also sometimes called coneflower or gloriosa daisy) cultivar that typically grows to 3’ tall on stiff, upright, leafy stems. It produces a long summer-to-fall bloom of large, daisy-like flowers (to 5” diameter) featuring orange rays tipped with lemon yellow and greenish center disks. Flowers bloom singly atop strong, sometimes-branching stems. Rough, bright green leaves (3-7” long) in basal clumps with smaller stem leaves. Species name of hirta means hairy in reference to the short bristles that cover the leaves and stems. Rudbeckia hirta is a Missouri native wildflower that typically occurs in open woods, prairies, fields, roadsides and waste areas throughout the state (see Steyermark). ‘Prairie Sun’ is an All-America Selection winner in 2003 and a Gold Medal winner at the 2003 Fleuroselect trials in England.
Problems:
No serious insect or disease problems. Susceptible to powdery mildew. Watch for slugs and snails on small plants. Taller plants may need staking or other support.
Uses:
Borders. Annual beds. Cottage gardens. Wild gardens. Meadows. Groups or mass plantings. Good cut flower.
© Missouri Botanical
Garden, 2001-2010
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