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Horticulture and Home Pest News
Horticulture & Home Pest News is filled with articles on current horticulture, plant care, pest management, and common household pests written by Iowa State University Extension specialists in the Departments of Entomology, Horticulture and Plant Pathology.

Visions of Coneflowers

This article was published originally on 8/25/1993
Coneflower is the common name ofseveral genera of plants including purple coneflower, Echinacea;prairie coneflower, Ratibida; and coneflower, Rudbeckia.Coneflowers get their common name from the central portion of theflower known as the disk. The brown to black disk area is made upof many small individual flowers. The disk area can be raised orcolumnar in shape. The outer portion of the flowerhead is made upof numerous ray flowers each containing a long strap-like petal.

Purple coneflower (Echinacea purpurea) is easy to growrequiring very little cultural input. It performs best in full sunand does not require fertilization. Flowers are 1 to 3 inches indiameter with brown central cones surrounded by rose to purplecolored petals. Flowering occurs from early summer until frost.Flowers are excellent used as fresh cut or the cones are used indried bouquets. The foliage of this plant is arranged alternatelyon the stem and coarse in texture. The leaves are 4 to 8 inches inlength, dark green in color with short stiff hairs. The plantgrows 2 to 3 feet tall and 2 feet wide. Some excellent cultivarsinclude 'Alba', 'Bright Star', and 'Robert Bloom'.

Prairie or yellow coneflower (Ratibida pinnata) is awildflower commonly found along roadsides, in prairie areas, andother dry spots. The plant grows up to 4 feet tall with slendergrooved stems covered with fine hairs. Leaves are alternate on thestem and are composed of 3 to 7 lance-shaped leaflets. Flowersoccur singly or in groups at the top of flower stems. The lightyellow ray petals arranged around the cone droop downward untilthey are almost parallel to the stalk. Flowers appear from June toSeptember. If you are looking for a plant to grow in a wildflowergarden, this plant is an excellent choice.

Coneflowers, also called black-eyed Susans, (Rudbeckia spp.)are commonly grown annuals, biennials, and perennials in the flowergarden. All have yellow to gold ray flowers and brown to blackcenters. Flowering begins in mid to late summer and continuesuntil fall. They grow best in full sun to part shade in ordinarygarden soil and tolerate hot dry conditions without any problem.Plants grow 1 1/2 to 3 feet tall with alternate leaves. Dependingupon the species, the foliage can be deeply cut or entire and isoften hairy. The flowers are good for cutting and produce a boldsplash of color in the garden. Excellent Rudbeckia cultivarsinclude 'Marmalade', 'Gloriosa Double Daisy', 'Goldsturm', and'Rustic Colors'.

Coneflowers, no matter what the genus, provide gardeners withlong lasting color and plant durability.

Purple Coneflower
Black-eyed Susan



This article originally appeared in the August 25, 1993 issue, p. 140.

Year of Publication: 
1993
Issue: 
IC-465(22) -- August 25, 1993