Purple Coneflower (Echinacea)

Bumblebee on echinacea.

You may have heard of echinacea if you frequent the vitamin&herb aisle in pharmacies and health food stores. While some Native American tribes used echinacea to treat cold symptoms, research has been inconclusive. Part of the reason why research is so challenging with this plant is that there are so many species, and the chemicals in the plant vary wildly from plant to plant. Like many other herbs, you can take it in many forms, and for different amounts of time. It does, however, make a lovely addition to the garden, for purely aesthetic reasons. It is also a boon to the pollinators, like various species of bees.

Warning: Echinacea may interfere with some prescription drugs! Harvard Women's Health Watch warns that it can cause major allergic reaction for people with asthma, or " Echinacea can be toxic to the liver, especially if taken for more than eight weeks, and therefore should not be used with other drugs known to be potential risks to the liver, such as anabolic steroids, amiodarone, methotrexate, and ketoconazole. In theory, immune stimulants like echinacea could counter the purposes of drugs like cyclosporine and corticosteroids that suppress immune function."

Some scientific research on Echinacea Purpurea and the common cold:

  • This is from a study on children:
    • "There was no significant difference in the mean duration fever, cough, rinorrhea and nasal congestion between echinacea and control group. Any adverse effect was not observed in our study. " 
    • Source: Rahmati, M. B., Safdarian, F., Hamedi, Y., Khadem, A. A., & Rezai, M. S. (2012). Efficacy and safety of Echinacea root extracts in the treatment of pediatric common cold: a randomised clinical trial. Journal Of Mazandaran University Of Medical Sciences, 22(93), Pe12-Pe18, En11.
  • This one comes from a study where they gave echinacea extract to people for four months, and compared them to people not taking it:
    • "Echinacea reduced the total number of cold episodes, cumulated episode days within the group, and pain-killer medicated episodes. Echinacea inhibited virally confirmed colds and especially prevented enveloped virus infections.:
    • Jawad, M., Schoop, R., Suter, A., Klein, P., & Eccles, R. (2012). Safety and efficacy profile of Echinacea purpurea to prevent common cold episodes: a randomized, double-blind, placebo-controlled trial. Evidence-Based Complementary And Alternative Medicine, 2012Article ID 841315

Other studies show that it works, that it doesn't work, etc., so the jury is still out. It may work only if you take it for a long time, etc. We just do not definitively know. The jury is still out, but gosh, it's pretty.

Purple and White Echinacea, gorwing in front of Joe-pye weed.