Knowledgebase
Possible Phythophthora in garden bed #869923
Asked May 24, 2024, 11:54 AM EDT
Genesee County Michigan
Expert Response
Short of sending the plants in, it's going to be difficult to exactly diagnose what might be going on there. The symptoms do lead me to believe there is a rooting issue here. The dieback on the flower stalks could simply be due to lack of support the plants are getting from their affected root system. I do see some white powdery residue that could be mildew or botrytis impacting the flower stalks, but that is likely secondary to what is going on with the root system. There is also some coloration the leaves that concerns me about possible virus infection (anemone and ranunculus can get Impatiens Necrotic Spot Virus, INSV).
https://gpnmag.com/wp-content/uploads/05_P&D_GPN0712%20FINAL.pdf
https://www.apsnet.org/edcenter/resources/commonnames/Pages/Anemone.aspx
I would suggest that you dig up and send in a couple of the plants (the entire plant, roots and shoots), one showing the worst symptoms, one just starting to show symptoms.
Here's where you can find the information about submitting the sample:
https://www.canr.msu.edu/pestid/submit-samples/
https://www.canr.msu.edu/pestid/uploads/files/General_Sample_Submission_Form_May2022.pdf