By Larry Hodgson
Question: I did a search on your site regarding the difference between an echinacea and a rudbeckia and couldn’t find anything. I was surprised because it seems like a beginner’s question to me and I’m certainly not the first person to ask. Have you ever covered this subject?
Diane
Answer: Actually, you are the first person who ever asked me this question. To be honest, I hadn’t even realized there could be any confusion. From my point of view, they’re clearly different, but then, I’ve been growing them ever since I was a child. To me, echinaceas are echinaceas and rudbeckias are rudbeckias. I’d be no more likely to confuse them than a farmer would confuse a sheep with a goat. It’s only as I pondered over how to answer your question that I realized: gee whiz, they really are very similar!
So, let’s take a look:
What They Have in Common
Although the two plants belong to different genera, Echinacea (10 species) and Rudbeckia (25 species), they’re in the same family, the Asteraceae, and in fact, from the same tribe in the family, so they’re very closely related. All species of both genera are herbaceous (there are no woody species) and most are perennials, generally quite cold hardy. They also come from the same area, being strictly of North American origin. Both form rosettes of basal leaves and bear upright flower stalks of varying heights. The inflorescences are very similar, with a daisylike composite flower head and a conelike center. As a result of this central cone, both are sometimes called coneflowers.
The cone is composed of fertile florets and is surrounded by “petals” (actually, ray flowers) of various colors. The two genera even bloom largely at the same season: most from mid- to late summer into autumn.
As for growing them, gardeners use both as ornamentals in flower beds and also in wildflower meadows and find them easy to grow, most doing best in sunny sites and well-drained soils. They attract pollinators, especially bees and butterflies. Neither is terribly subject to predation from deer or rabbits. And both make great cut flowers.
How They Differ
For a long time, it was easy enough to tell echinaceas from rudbeckias by the color of the ray flowers. Echinaceas as grown in home gardens either had pink or white flowers, while rudbeckias had yellow blooms or yellow overlaid with orange, red or brown. There had always been a wild yellow echinacea (E. paradoxa), but few people grew it.
Then in the early 2000s, new hybrid echinaceas in a wide range of colors—red, orange, yellow, white, pink, green and purple—first appeared on the market. From then on, the “pink/white compared to yellow” distinction no longer held.
However, what about cone color? Many of the rudbeckias have dark cones: brown or nearly black, and so have been called black-eyed or brown-eyed Susans. Echinaceas never have black cones or extremely dark ones and mostly range from orange to green to mahogany brown, often changing as the flowers mature.
Of course, it turns out there are also rudbeckias with green cones, but if so, they’re usually a bright green.
True too, double varieties of both show no cones at all … but the double ones start out with a cone … it only becomes covered with ray flowers over time, so that does leave a window of opportunity for identification.
Close up, touch the cones. This is the real giveaway. The very name Echinacea means “hedgehog” (from the Greek echinos) and the cones are covered in spiky appendages called paleae, so they’re prickly. Rudbeckia cones, though, are never prickly.
So, the best way to tell the two apart is to compare cone color and, for even more certainty, texture.
And Then Came the Echibeckias
Just when some semblance of simple classification seemed possible, a new class of plants came along that threw all logical differences out the window.
For a few years now, hybrids between Echinacea and Rudbeckia, called × Echibeckia, have been available to home gardeners. They’re a cross between, I’d guess (because their parentage is a closely guarded secret), the short-lived species Rudbeckia hirta, which they resemble enormously, coming in the same yellow, orange and red shades, with the same near-black cone, and who knows which Echinacea. They’re like a more reliably perennial Rudbeckia hirta, really, and are hard to tell from that plant. They’re sterile and can’t be multiplied by seed.
So…
You still can generally tell echinaceas from rudbeckias by the spikier, non-black cones of the former and dark, smoother cones of the latter. But you’d be hard-pressed to tell an echibeckia from a rudbeckia.
© 2021
Just happened upon your site as I didn’t know the difference either. Your rather rude reply saying you can’t believe there could be any confusion and that it’s like a farmer confusing a goat and a sheep made me see that you are one of this prima Donnas who acts like an ass to show everyone you’re an expert. Trust me. I won’t be back for any information from you. There are plenty of others who willingly share information without trying to make the student look like am idiot.
I didn’t find his first paragraph rude at all, just an explanation that he hadn’t realised the difference wasn’t obvious to everybody and I found the explanation of the differences very helpful.
You won’t get any information from him Jilly. He died in 2022.
I LOVED this article! So informative and easy to read! At almost 56 and never able to keep anything alive other than my children (who alerted me when they were hungry, too dry, too wet) I decided to plant a packet of “wildflower seeds” and was thrilled to find out those weedy looking things were indeed Susans and bloomed beautifully. Now I’ve noticed pink flowers that look similar so I was researching if there are “pink Susans”. I learned so much about my first success! Thank you!
They’ve both always been pretty common here in Maryland, with the Black Eyed Susan being our state flower; but how does one distinguish them Before they bloom?!
Very helpful. I enjoyed this article. Thank you. I have pretty 2.5 feet high deep orange/rust coloured echinaceas which fade to a pretty pink and last most of the summer. I also have robust yellow echinaceas which grow to six+ feet and put on a splendid show from about August 5th to mid-October when the frost finally gets them. The yellow plant(s) fill a bed about 4′ x 3′. In the spring I trim about 1/3 of the leaves back a bit when the plants are about a month old and another 1/3 a month later, so there are always new flowers when it comes time to bloom. All stems keep producing new flowers, if you deadhead them. The cheerful Rudbeckias are pretty faithful showing up each year.
I have both in my garden, and I need help distinguishing the baby plants. I want to encourage echinacea and limit my rudbekias. The leaves look the same. Any clues?
Also Echinaceas bloom before Rudbekias, at least here in my garden. But how can you tell them apart in the spring? I can never tell them apart when the leaves are young.
Actually, bloom times do vary! The leaves are different, but each species (especially in the case of rudbeckias) differs from each other too! You’ll just have to stick in some plant labels when they are in bloom!
Info. helpful for experienced gardener who gave up lights and heat pad due to lack of room now. So now I will try winter sowing. But had to look for what zone you were giving info. for. Thanks.
Very good article, puts other ID articles to shame as they typically ID echinacea by color: purple or white. And of course purple is really a pink, to me anyway. Very helpful, thanks.
Thank you! ?
Echinacea was rare here before it became a fad. Rudbeckia was uncommon also, but of the two, was the only one I had ever met. I thought that Echinacea was just a fancier version.