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Natural Remedy - Summer 2010
Coneflowers, from the ubiquitous to the rare, are known for their visual as well as their medicinal appeal
Story by Bibi Wein
Tennessee purple coneflower (E. tennesseensis) is endemic
to the Nashville area. Photo by Stefan Bloodworth
In the wild, coneflowers are found in a range of habitats from prairies to open woodlands and savannas, often growing in dry, rocky or sandy soils. Most of the nine species and two variants native to North America hybridize when brought together under cultivation. Their annual stems rise from underground perennial roots – a single taproot for all except the familiar purple coneflower (Echinacea purpurea), which has a fibrous root system. At some blossoms’ center is a large, spiny “cone” – in some species wider than the ray flowers are long. It is from the cone’s bristly character that the plant gets its name: Echinos means hedgehog in Greek.
South Dakota rancher and eminent plantsman Claude A. Barr, in his 1983 classic, “Jewels of the Plains,” called narrow-leaved coneflower (E. angustifolia) “bold, spectacular and beautiful.” Hardy in USDA zones 3-8, at an average height of 18 to 25 inches, it’s one of the shorter and more compact echinaceas, with light-pink to pale-purple rays spreading outward from an orange-brown cone. With the widest native range, through the center of North America from New Mexico, Texas and Louisiana north through Manitoba and Saskatchewan, this June to July bloomer, also known as Blacksamson coneflower, was an important medicinal plant for many native tribes. Comanche women traditionally collected E. angustifolia seeds and distributed them throughout their buffalo hunting grounds so they’d have the plant for medicinal use wherever they traveled. [E. angustifolia var. strigosa is native only to a narrow band that runs from south-central Kansas through central Oklahoma and northeastern Texas. It has a more branching habit, a wider disk and darker, almost reddish ray flowers.]
But for contemporary gardeners, purple coneflower (E. purpurea) and its many cultivars tend to eclipse E. angustifolia and other echinaceas. The sturdy disk-shaped blooms – not true purple but pink, rose, or magenta – are prized for their size and showy color and make perfect landing pads for butterflies. Hardy in USDA zones 3-8, it has smooth stems and dark-green heart-shaped leaves.
I grow coneflowers in three places around my log cabin in northern New York, and they’re an asset of a different kind in each location.
On the sunny south side of the cabin, in a bed where I’ve done virtually nothing for more than a decade but spring clean-up and occasional watering, E. purpurea and E. pallida are late-summer stars. After most of the phlox is gone and the lilies are long passed, the coneflowers – at least 4 feet tall, accompanied by goldenrods, coreopsis and small white asters (Symphyotrichum lateriflorum) – take over.
In another sunny bed, E. purpurea shares space with vegetables, never minding the shade when neighboring tomato plants get tall and bushy.
Blacksamson (E. angustifolia) is one of the primary species
(with E. purpurea and E. pallida) used in commercial medicinal
echinacea products today. Photo by Lillian G. Flaigg
But it is in the light shade of a shallow hill, where many of my plantings have struggled or failed, that echinacea has been the greatest boon. The soil is sandy and so dry that no amount of amendment, nor any of the terracing I’ve provided, will get it to hold moisture. It’s E. purpurea that keeps the area looking like a garden.
More than halfway across the country, Andrea DeLong-Amaya, director of horticulture at the Lady Bird Johnson Wildflower Center, extols the virtues of the same plant. “Since purple coneflowers are so reliable for us, we have them planted in many areas of the gardens,” she says. “E. purpurea is planted in all combinations with other plants including mealy blue sage (Salvia farinacea), black eyed Susan (Rudbeckia hirta), gulf muhly (Muhlenbergia capillaris), and others. For us they typically bloom mid-spring and into the summer if we’ve had rain, and again in the fall until it freezes. They may actually bloom for us all summer, but they’ll be sparse. Big shows are spring and fall.”
Pale coneflower (E. pallida) native to the East and parts of the Midwest, is one of the most under-appreciated of the echinaceas, according to Jeanne Frett, horticultural research manager, and horticulturist Victor Piatt, of the Mt. Cuba Research Center in Greenville, Delaware. I understand why. When I first saw it, the pallor and downward turn of its slender ray flowers impressed me as an unhappy E. purpurea.
Talking to Frett and Piatt quickly persuaded me to see its delicate form and kinetic potential as an asset. “I like E. pallida for the subtlety of all its characteristics,” says Piatt. “And the ray flowers of our plants, instead of horizontal, are narrow and drooping, and sometimes they have a lovely little twist. In the slightest breeze, the whole flower moves, and sometimes the ray flowers move separately. It’s much more animated than E. purpurea, which is very rigid in form.” He points out that the foliage, blue-green to blue-gray and linear, adds still another design element, in both color and shape.
Hardy from USDA zones 3-10, pale coneflower’s coppery-orange cones contrast dramatically with ray flowers that range from near white to pale-pink or lavender. It does best in full sun, and while it will survive in partial shade its flowers may suffer.
“There’s a great deal of emphasis, especially in cultivars and hybrids, on the size and color of the flowers – the bigger and brighter the better,” adds Frett. “And sometimes the gracefulness of the species is lost.”
Frett and Piatt have recently completed a three-year study in which they observed 48 echinaceas (five of the nine species and 43 cultivars) in a trial garden designed to reflect conditions in a typical home garden in the mid-Atlantic states (USDA Hardiness Zone 7A-6B).
“I’m for the unsung species,” says Piatt. “All the species with drooping petals, not just E. pallida but E. atrorubens, E. sanguinea, E. simulata and E. paradoxa, are much more animated in the garden.”
All of these except for E. paradoxa and E. laevigata have hairy stems and foliage – a deterrent to leafhoppers. The Aster Yellows disease these insects cause was virtually the only insect problem encountered in Mt. Cuba’s echinacea garden. “And it didn’t seem to be as prevalent in the hairy-stemmed species from our observations,” says Frett.
Pale coneflower has several look-alike species, including wavyleaf coneflower, E. simulata, which is virtually identical but hardy only to USDA zone 5, E. angustifolia, which doesn’t get as tall, and sanguine purple coneflower, E. sanguinea, an early bloomer, generally flowering in May and found in more acidic sandy soils and open pine woodlands. Echinacea pallida is the only coneflower with white pollen.
Smooth purple coneflower (E. laevigata) blooms May
through July. Photo by Stefan Bloodworth.
One of the most beautiful coneflowers of all is the only one that is not purple, even though Bush’s purple coneflower is one of its common names. Sun-loving yellow coneflower (E. paradoxa) starts blooming in early June and is typically 3 feet tall, with very large coppery to chocolate cones. Like all echinaceas it is very drought-tolerant, and some may rebloom sporadically all summer. Native to Arkansas (where it is threatened), Missouri, Oklahoma and Texas, it is hardy in USDA zones 5-8. A variety, E. paradoxa var. neglecta, endemic to south central Oklahoma, has the same bright-green stems and yellow pollen as E. paradoxa but has white to pale-pink or pale-purple ray flowers more like E. pallida.
Three of the nine echinacea species are endemics. Topeka purple coneflower (E. atrorubens) grows only in a narrow region running north to south along the eastern grasslands of Texas, Oklahoma and Kansas. It is characterized by deep-magenta flowers and a cone as large, or larger than, the length of the ray flowers.
Most people aren’t aware of the two federally endangered coneflowers. Smooth coneflower, E. laevigata, is closely related to E. purpurea but distinguished by smooth ovate leaves and flowers with a color range from white to deep magenta. Its range is limited to Pennsylvania, Virginia, the Carolinas and Georgia in open habitat with low competition. Tennessee coneflower, E. tennesseensis, is found only within a 14-mile radius in the growing urban sprawl of Nashville. It’s one of our rarest wildflowers and was the second plant to be listed as endangered by the U.S. Fish and Wildlife Service in 1979. Similar to E. purpurea but shorter and with cup-shaped ray flowers, it has an extraordinarily long bloom period, from June to August.
Many purple echinaceas look stunning in the company of strong yellow flowers, including the yellow coneflower. Their clean lines contrast agreeably with the frillier Achillea millefolium (yarrow) and the delicacy of small white asters. If you can grow orange butterfly weed (Asclepias tuberosa – USDA zones 5 and up), its bloom time is likely to coincide with purple coneflower for a striking color contrast. Other fine late-summer coneflower companions are virgin’s bower (Clematis virginiana), Spiraea spp. (white to pink), red beebalm (Monarda didyma) and the deep purple ironweeds (Vernonia spp.). Plant any combination of the above and you have a butterfly garden that may attract hummingbirds and other wildlife.
“Goldfinches like the seeds, “ says Piatt, “and mourning doves seem to like the cover. Also, I’ve found toads digging in and around coneflower roots, and I let them stay because they are totally doing their job by eating slugs.”
All echinaceas self-pollinate to some extent, but the major pollinators are insects, especially bumblebees and butterflies like royal frittilary, great spangled fritillary, monarchs, swallowtails and painted lady.
Among my many mental snapshots of guests enjoying our outdoor space, one stands out: Our visitor was admiring a purple coneflower when a monarch butterfly landed on the mature russet cone and began to feast. The look on his face was transformed to one of a child’s pure wonder. More than a decade later, this image returns to move me anew at the end of every summer when the coneflowers bloom.
Bibi Wein authored The Way Home: A Wilderness Odyssey (Tupelo Press) about the Adirondacks.