Japanese Lilac - Not healthy. Help!

Asked August 12, 2020, 1:39 PM EDT

Landscaper planted this Japanese Lilac (7 feet tall - was a large potted) about 6 weeks ago, just before all the hot weather. Looked full and healthy. It was recommended daily watering for first 1-2 weeks, then every 2nd or 3rd day after that. Give roots a good soaking. Gets 5-6 hours sun per day. Has been steadily loosing leaves and many existing leaves showing brown spotting. See attached. Could this be a fungus? Too much or too little water? Advice appreciated Steve Budnik

Carver County Minnesota

1 Response

It is probably infected by the bacterial blight of lilacs running rampant this year. It rarely kills the lilac and good sanitation will reduce it next year.
Another possibility is anthracnose, a fungal disease that is more common in humid wet weather.

For an accurate diagnosis samples can be sent to the plant disease clinic.