Two plants side by side: 1) Echinacea ‘green twister’ has looked relatively healthy all summer but never developed petals on the flowers and recently I notice green tufts sticking out of the seed cone. 2) Achillea ‘moonshine’ looked fantastic and full of flowers until a few weeks ago it started thinning out with discolored leaves and stopped setting flowers. Is this aster yellows? If it is, do I need to treat the remaining plants in the area to prevent it from spreading? I know the plants already with the virus would need to be destroyed if this is aster yellows.
Oakland County Michigan
Echinacea are susceptible to aster yellows. Once a plant is infected, there is no cure. The recommendation is to dig out infected plants and destroy them. Do not put them in your compost bin. The disease is spread by insects, primarily leaf hoppers. Getting rid of the infected plants helps prevent Aster Yellow from spreading to other susceptible plants in your garden.
Or, the Eriophyid mites are microscopic in size and live inside of the buds where they feast on the nutrients. The damage will result in the flowers forming with distorted, wilted petals. Once infected the recommended to dig out and destroy the affected plants.
You may see aster yellow again in the garden. Plants seen distorted, stunted and or with unusually lighter green stems and leaves just pull diseased plants out to control the spread. For more information see: