Cone Flowers with Aster Yellows or Rosette Mites

Asked July 7, 2018, 2:45 PM EDT

Hi there! I sadly just pulled 99% of my cone flowers because they either have Aster Yellows or rosette mite.... I couldn't tell. I have some questions regarding this problem... 1: All the affected flowers were growing in a mess of flowers planted around an old tree stump. This prevents me from getting all the roots and lower foliage of the cone flowers (I did my best). My garden is full of susceptible plants like rudbeckia, daisies, zinnias, and other... How do I prevent the spread without being able to remove all the debris and roots? 2: can I replant coneflowers for next year? Or should I avoid them? 3: How do I tell if my other plants have Aster Yellows? And if the problem was the Rosette Mite, does that affect other perennials? Sorry for the complicated post.... Thanks for your help! My email is erincmetz@gmail.com My phone is 651-900-5471

Ramsey County Minnesota

1 Response

Hello and thank you for contacting AaE for help.

Aster Yellows (AY): If the lower foliage of the affected plants are still there and viable, there is a chance that a leaf hopper can become infected by the plant and then go on to infect other plants. There is a long list of plants that can contract AY from an infected leaf hopper. Once that lower foliage dies, it is no longer a danger. If, when removing plants, you remove enough of the roots so that it cannot sprout again, then it is no longer a danger. In that case, you can plant again in the same location where the infected plant was removed both now and next year.

Rosette mite: The eriophyid mite causes distorted plant parts. According to the Missouri Botanical Gardens website, the damage is cosmetic and not deemed fatal to the plant. You could cut out and destroy the damaged parts if you think that is the issue with your plants. Also, be sure to clean up all parts of the plant from the area in the fall. Here is a link to the Missouri Botanic web page on eriophyid mites for more information and identification help.

I hope this information helps.