Coneflowers, those hardy biennials and perennials most known for their yellow and purple varieties, are easy to grow. The two types of cornflowers best known to gardeners are black-eyed Susans (Rudbeckia spp.), with yellow petals and black cone-like centers, and purple coneflower (Echinacea purpurea), also known as echinacea, with purple petals and brownish-red centers that rise to a peak.
The name Echinacea comes from the Greek word echinops, or hedgehog, apparently because of the spiky bristles at its center. The botanist Carolus Linnaeus named the yellow coneflower after professor Olav Rudbeck. Most people attribute Rudbeckia's common name to the early 1700s poem "Sweet William's Farewell to Black-Eyed Susan," by John Gay.
The Plains Indians used powdered root of purple coneflower as a kind of all-purpose antibiotic to treat rabies and snakebite.
The black-eyed Susan became Maryland's state flower in 1918. Many state residents protested the choice because they considered the flower a common weed. Supporters from the Maryland Agricultural College prevailed, pointing out the plant's black-and-gold coloring corresponded with Lord Baltimore's coat of arms.
Some yellow coneflower hybrids are double-flowered, while others, like the common variety, are single-flowered. A few varieties, including Rustic Colors and Prairie Glow, are red or burgundy rather than yellow. Because so many black-eyed Susans and hybrids exist, make sure to check your variety's height--they range from 1 to 4 feet tall.
Purple coneflowers generally reach 4 feet. Like rudbeckias, echinaceas now come in a variety of colors, from the common purple to pink, red and white. Their rust-colored centers are indeed cone-like and rise above the petals. Most coneflowers are hardy to
USDA zone 3.
Both rudbeckias and echinaceas make for carefree cultivation in a perennial bed. They prefer full sun, although purple coneflower will also thrive in part shade. They bloom in mid to late summer, and spread somewhat aggressively. Divide them every few years to keep them healthy and prevent them from taking over the garden. They do not need any special fertilizers or treatment, and dislike over-watering. Black-eyed Susans make good rock garden plants.
Commercial Cultivation of Purple Coneflower
Since echinacea supplements became synonymous with cold prevention during the 1990s, commercial echinacea farms have sprung up around the United States, especially in the Midwest. U.S. manufacturers typically focus on herbal supplements, made from the whole root, while European growers supply all parts of the fresh plant to manufacturers of topical applications.
Purple Coneflower Root
Herbalists prize dried echinacea root for its use in skin creams and lotions. "Echinacea is the herb of choice for antimicrobial action," says author Dina Falconi, who specializes in herbal skin treatment. "Echinacea can be both ingested and applied topically where acne and other puslike activity is occurring." Interestingly, the root's potency can be measured by how much it makes the tongue tingle and "vibrate" when a bit of the root is placed upon it, Falconi says.