By Reshmina William, PhD in Civil Engineering at UIUC, RORG Volunteer
In late spring and early summer, the vibrant blooms of pale purple coneflower will bring a dash of showy color to our rain garden. However, this particular species is more than just a pretty face. Together with its other coneflower cousins, Echinacea pallida is a vital part of a healthy native ecosystem, both above and below the surface of the landscape.
The word Echinacea means “hedgehog” in ancient Greek, and indeed the plant’s spiky central “cone” is easily its most distinguishing feature. However, more than half of a healthy coneflower’s bulk lies beneath the ground surface. Coneflower taproots can extend up to five feet underground: nearly 12 times further than the root system of a typical lawn. These deep taproots ensure that coneflowers are hardy plants, tolerant of heat, drought and humidity. Within a prairie ecosystem, deep roots not only help to hold soil in place, but can serve as a “conveyor belt” bringing up water from deeper within the soil for more shallow rooted plant species.
Coneflowers as a family have evolved to thrive on native prairies, being grazed by animals or undergoing routine burns as a result of lightning-sparked wildfires. Now, however, some species of coneflower are threatened in parts of their range as a result of habitat destruction. The over-collection of coneflower roots for herbal remedies also contributes to the problem. Within the Red Oak Rain Garden, our pale purple coneflowers will provide a glimpse of a flourishing prairie habitat: keeping soils healthy, providing sustenance for native pollinators, and offering beautiful blooms that everyone on campus can enjoy.