I have a home garden which I think has a fungus or some sort of infection. It started on the left side with my hydrangeas and has slowly spread to my other perennial flowers. It start with these red spots on the hydrangeas, the leaves get shriveled up and stop growing. The plant itself doesn’t grow. This has spread to my other plants where they get these spots on them. I would like to get some advice as to what this is and how to fix it. I have tried Neem oil, copper fungicide and no luck. I remove the leaves of the infected plant immediately and it still spreads. 🙁
The first step is to get a proper diagnosis. The leaf spots on the hydrangeas are not the same pathogen as the leaf spots on the perennials. Submit questions and photos to the HGIC at University of Maryland here : https://extension.umd.edu/programs/environment-natural-resources/program-areas/home-and-garden-information-center/ask-extension.
They will be able to guide the homeowner as to what and when to spray or if there is an another treatment or prevention to be used.
For the hydrangeas, planting resistant varieties is the best approach. Here is a guide to managing the leaf spot on the existing hydrangeas: https://www.uaex.uada.edu/publications/pdf/FSA-7570.pdf
They will need to submit samples (pictures) for the perennials as the diseases occur