Rudbeckia 

(rude-beck' ee-ah)

Common name: Coneflower, Black-eyed Daisy/Susan/Susie

Family: Asteraceae, Aster

Height x width: 2-8' x 2-3' depending on species

Growth rate: moderate to fast

Foliage: alternate, entire to slightly toothed or deeply cut, basal leaves ovate, upper leaves oblong, 3-6" long

Flowers: yellow to golden rays and brown to black centers, 3-4" wide, mid to late summer, on long leafless stems (peduncles)

Hardiness: zones 3-5 to 8-9

Soil: well-drained, tolerates dry

Light: sun

Pests and Problems: downy mildew, rusts, leafspots, powdery mildew, crown rot, leaf gall, smut, aphids, beetles, four-lined plant bug (none usually serious)

Landscape habit, uses: borders, cut flowers, bees and some species attract butterflies, native areas, wildflower garden

Other interest: native to N. America; named for 18th century Swedish botanist Olaus Olai Rudbeck by Linnaeus in 1753 to commemorate his former teacher; should not be confused with other perennial coneflowers Ratibida and Echinacea

Other culture: tall species need staking

Propagation: seed (70,000 seeds per ounce), division, terminal cuttings in summer

Species:

fulgida (ful-gi-dah')--Orange Coneflower, 18-36", zones 3-8, native to southeast U.S., forms large clumps and spreads

laciniata (la-sin-ee-aa' tah)--Cutleaf Coneflower, 3-8', zones 3-9, native to much of the U.S. in moist fields and roadsides, often planted as a screening plant in New England, rough stems

maxima (max-i-mah')-- Giant Coneflower, zones 5-9, 5-8', native to much of the U.S., large leaves to 2' long and 10" wide and blue-green, long black cylindrical cones, propagate by root cuttings

nitida (ni-ti-dah')-- zones 6-8, native to the South, similar to laciniata only 3-5' tall

subtomentosa (sub-to-men-to' sah)--Sweet Coneflower, zones 5-9, 3-4', native to much of the U.S., similar to triloba only flowers have faint anise scent, stems are softly downy, and cones are dull purple-brown

triloba (tri-low' bah)-- Three-lobed Coneflower, zones 3-9, 3-4', native to much of the U.S., basal leaves are three-lobed, usually perform as a biennial, may self-sow (photo courtesy photobucket.com, carrie630)
 
 

Cultivars:
 
Cultivars, other taxa species flowers height other
'Autumn Sun':'Herbstsonne'        
'Gold Drop':'Goldquelle'        
'Gold Fountain':'Goldquelle'        
'Golden Glow' laciniata lemon yellow, double 4-6' nitida hybrid
'Goldquelle' laciniata yellow, double 2-4'  
var. deamii fulgida yellow 2'  
'Herbstsonne' laciniata sulphur yellow, green disc 6-8' nitida hybrid
var. hortensia:'Golden Glow' laciniata      
var. speciosa fulgida deep orange, 2-3" wide 24-30"  
var. sullivantii 'Goldsturm' fulgida deep yellow, 3-4" 18-24" very popular
         

('Goldsturm' photo courtesy Missouri botanical gardens plantfinder; Golden Glow photo courtesy leishasbackyardhabitat.com)


©Authored by Dr. Leonard Perry, Professor, University of Vermont as part of PSS123 course.

Return to  Perry's Perennial Pages | HGPO course | PSS123 course