Biennial or short-lived perennial that is winter hardy to USDA Zones 3-7. It blooms in the first year from seed planted in early spring, and is accordingly often grown as an annual. It is easily grown in average, medium moisture, well-drained soils in full sun. Best in moist, organically rich soils. Tolerates heat, drought and a wide range of soils except poorly-drained wet ones. For best result from seed in the St. Louis area, start seed indoors around March 1. Seed may also be sown directly in the garden at last frost date. Some varieties are available in cell/six packs from nurseries. Set out seedlings or purchased plants at last frost date. Deadhead spend flowers to encourage additional bloom and/or to prevent any unwanted self-seeding. Whether or not plants survive from one year to the next, they freely self-seed and will usually remain in the garden through self-seeding.
Ruudbeckia hirta, commonly called black-eyed Susan, is a common Missouri native wildflower which typically occurs in open woods, prairies, fields, roadsides and waste areas throughout the State. It is a coarse, hairy, somewhat weedy plant that features daisy-like flowers (to 3” across) with bright yellow to orange-yellow rays and domed, dark chocolate-brown center disks. Blooms throughout the summer atop stiff, leafy, upright stems growing 1-3’ tall. Rough, hairy, lance-shaped leaves (3-7” long). Plants of this species are sometimes commonly called gloriosa daisy, particularly the larger-flowered cultivars that come in shades of red, yellow, bronze, orange and bicolors.
Genus name honors Olof Rudbeck (1630-1702) Swedish botanist and founder of the Uppsala Botanic Garden in Sweden where Carl Linnaeus was professor of botany.
Species name of hirta means hairy in reference to the short bristles that cover the leaves and stems.
‘Prairie Sun’ 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. ‘Prairie Sun’ is an All-America Selection winner in 2003 and a Gold Medal winner at the 2003 Fleuroselect trials in England.
No serious insect or disease problems. Susceptible to powdery mildew. Watch for slugs and snails on young plants. Can self-seed freely.
Borders. Annual beds. Cottage gardens. Wild gardens. Meadows. Groups or mass plantings. Good cut flower.