Coneflower (Echinacea purpurea) is an herbaceous perennial commonly referred to as the purple coneflower. Today the coneflower comes in a variety of new, bright and bold colors. Coneflower is a long-blooming prairie wildflower closely related to the rudbeckia. The flowers bloom plentifully starting in midsummer until the first frost.
The daisy-like flowers can grow up to 3 inches across, have attractive petal rays, and large, cone-shaped purple-brown centers. The common name purple coneflower is becoming misleading as new cultivars have produced new flower colors. Flower colors now include red, orange, green, yellow, and even a bi-colored purple with a green-tipped petal.
Leaves are deciduous, a darker shade of green, and rough, like sandpaper. They are lance-shaped and 3 to 8 inches long. The leaves are arranged alternately on the stem and are a simple leaf type. There is no fall color change or showy characteristics.
Coneflowers do best in full sun but can tolerate part sun. They prefer humus-rich, well-drained, moist soil. They are hardy in zones 3 to 9. Coneflowers can be started from seeds or divided by the root in early spring. The coneflower does well if mulched to protect its shallow roots from drying out. Deadheading prolongs the blooming life of the plant. Coneflowers are clump-forming, making root division easy. They should be divided every couple of years to keep plants healthy and blooming.
The rigid look of the coneflower contrasts well with the softness of other perennials or fine-textured plants. Coneflowers attract attention because of their amazing flowers. They make nice complements in a mixed border. They also do well in afternoon shade in late summer. Protection from the hot afternoon sun promotes flowers and keeps leaf color green.
Coneflower pests include sweet potato whiteflies and Japanese beetles.
It is important to identify sweet potato whiteflies because their predisposition to control measures is different from other whiteflies. They live and feed on the underside of leaves by piercing the plant tissue and sucking the sap out with their biting mouth parts. The damage done by these whiteflies can result in the growth of a sooty black mold. Other damage includes plant breakdown, yellowing of leaves, leaf shredding, and infection with the vector virus, which is carried by the sweet potato whitefly.
Japanese beetles eat leaves and flowers. They feed in groups beginning in June. They start at the top of the plant and work their way down. The group feeding is what causes the severe damage. They chew out the tissue between the veins and can completely consume petals and leaves. They are fast-moving and can infest new areas quickly.