What could be eating my coneflowers? Little, tiny holes all over all the leaves - I can't see anything.
Coneflowers are subject to many insect pests. Among the most damaging are aphids and leafhoppers. Aphids damage plants by causing stem dieback, wilting, and foliage discoloration. Leafhoppers leave spots on the foliage, cause leaf distortion and flower drop. Both types of insects can quickly suck the sap/juices from plants and leave them susceptible to disease. Treating the plants with neem oil can help. Here is more information: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
The petals of my coneflowers are being eaten, often leaving just the center. What could be doing this, and how do I stop it?
Here is an article that you may find helpful: https://www.gardeningknowhow.com/ornamental/flowers/coneflower/coneflower-problems.htm
Some plants have flowers with no petals- just the ball. Is this another variety of the coneflower? Sometines the plant has both petaled flowers and the balls. Otherwise, it looks healthy.
I think what you are seeing are spent (completed) flowers. Cut the seedheads (what you refer to as balls) off to extend the season of your coneflowers.
I had 3 small coneflower plants that I planted in the ground in November. They have grown really big and are healthy looking; however, they haven't had any flowers yet. What could be the problem?
You may need to add more phosphorus to the soil. Here is more information: https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/phosphorus-plant-growth.htm
I live in SW Michigan. Have always had great luck w/Coneflowers, but this year all 3 (different varieties) are displaying the same problem. The buds turn brown and do not open up! My purple and orange coneflower plants managed to produce blooms initially but are now doing the same thing that my yellow one is. Some appear to have partially developed a petal or two but then just seem to halt and turn brown. Others are just completely brown over. No change in my watering habits, has been very humid here this summer and a bit dry over the past few weeks. I usually water if things tend to get super dry. The foliage looks fine to me. These have always been nearly maintenance free and easy to grow. . . any thoughts on what it might be?
They may be suffering from an infestation of Eriophyid mites, which live and feed on the insides of flower buds. Damage can be recognized by stunted growth and distorted flowers. Simply remove affected plants and hopefully, this will take care of the issue.
Another possibility is aster yellows disease. On coneflowers, the most typical symptom is replacement of flowers by tufts of small, green, deformed leaves. No treatment is available to save a plant infected with aster yellows. Aster yellows is best managed by removing infected plants from the garden to minimize spread.
I have heard that they are still healthy, but I don't know what I can do to get full petals. . . some have almost none at all.
It is possible that the coneflowers are being affected by Eriophyid mites, which live and feed on the insides of flower buds. Damage can be recognized by stunted growth and distorted flowers. Treatment of these insect pests can usually be achieved with insecticidal soap sprays or neem oil. I actually like the latter, as it is also an effective fungicide should any other issues pop up as a result of the insects. Here is more information: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
Another possibility for the distorted flowers in a disease called Aster yellows, which can actually be transmitted through insects. Here is more information: https://www.gardeningknowhow.com/plant-problems/disease/aster-yellows-disease.htm
I have several varieties of coneflowers in my garden in Delaware. The buds form fine; however, as the petals develop, they either shrivel or get eaten by something. I have sprayed with insecticide and put slug bait down but nothing seems to help. What could be causing this? It's been extremely HOT and I wondered if that could be a cause.
Treat the plant with neem oil. It will take care of most insect pest issues and is an effective fungicide as well. Here is an article that you may find helpful: https://www.gardeningknowhow.com/ornamental/flowers/coneflower/coneflower-problems.htm