Dear all, I have a question about my amelanchier lamarckii. I bought a multistem one around 200$ in winter and planted it out. I pruned it a bit after flowering to show the stems a bit more. Cuts were really not bigger than 1 cm per branch, it were mainly smaller branches. It put tree in new soil (garden mix with compost etc... bought from a specialized firm) and put soil improver (organic matter) in the ground as well. We had about 1 week of heavy heavy rain in May and now my tree is covered in powerdy mildew. I sprayed some fungicide on a dry day... but doesn't seem to do much. Pictures are a bit blurry, sorry for that. Is this anything I should worry about?
