Common Name: black-eyed Susan
Type: Herbaceous perennial
Family: Asteraceae
Zone: 5 to 9
Height: 4.00 to 7.00 feet
Spread: 2.00 to 3.00 feet
Bloom Time: June to August
Bloom Description: Yellow
Sun: Full sun
Water: Medium
Maintenance: Low
Suggested Use: Rain Garden
Flower: Showy
Attracts: Butterflies
Tolerate: Deer, Drought
Culture
Best grown in average, evenly moist, well-drained soils in full sun. Tolerates hot and humid summers. Tolerates some drought once established. Deadhead spent flowers to encourage additional bloom. May flop and require staking in rich, fertile soils. Divide clumps every 4-5 years to maintain robust growth.
Noteworthy Characteristics
Rudbeckia is a genus of about 20 species of annuals, biennials and perennials from North America. They are grown for their showy, daisy-type flowers which usually feature a dark, central eye of disk florets ringed by yellow ray florets.
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.
'Herbstsonne' is an upright, rhizomatous, clump-forming perennial coneflower which typically grows 4-7' tall. This is a substantial plant which features large daisy-like flowers (3-4" across) with drooping yellow rays and elongated bright green center cones. Flowers bloom singly atop slender branching stems. Long summer bloom. Toothed, bright green leaves (3-6" long). 'Herbstsonne' is varyingly sold as a cultivar of either Rudbeckia nitida or Rudbeckia laciniata, however some experts maintain that it is actually a hybrid between the two species. 'Herbstsonne' is synonymous with 'Autumn Sun'.
Problems
Watch for aphids, powdery mildew, downy mildew, and septoria leaf spot. Susceptible to aster yellows disease.
Uses
Massed or grouped in mixed perennial borders, cutting gardens, cottage gardens, and native plantings.