I'm in SouthEast Pennsylvania, near the Delaware border. In a house we just bought, was overgrown very badly. After a YEAR of weeding, I now have a pretty cleaned-up garden, and some diseases to take care of.
I have two nice old lilacs that are showing signs of disease as they are emerging in this current sunshine. New growth is pale, wimpy green, with black edges that spread. Last year I noticed whole branches turning black.
I am thinking Pseudomonas (lilac blight), and/or powdery mildew. I have done some Penn State U. research, recommending spraying mancozeb and copper together, to potentially take care of both. I realize that spring damage is damage for the year. Will try to treat better next spring, now that I know about the disease.
Can anyone recommend a recipe for this disease, including possibly mancozeb and copper? (there is a product called ManKocide, but it doesn't seem to be available here).
These are very large lilacs, and I'd like to save them. Any advice?
