Lilac disease - Ask Extension
We had a beautiful bloom on our mature lilac this year but now it's leaves are covered with brown splotches. We've noticed another lilac in the neighb...
Knowledgebase
Lilac disease #878728
Asked July 25, 2024, 12:28 PM EDT
We had a beautiful bloom on our mature lilac this year but now it's leaves are covered with brown splotches. We've noticed another lilac in the neighborhood with the same condition. Is it a fungus or some other type of disease? Is it treatable and, if so, how? We have noticed beautiful bright green new leaves where we pruned it a month ago. Does it need rejuvenation? Would that solve the problem?
Thank you in advance for your help and advice.
Freeborn County Minnesota
Expert Response
Lilac blight is widespread this year - likely due our large amount of rain. There is bacterial and fungal blight. Start with picking up any debris from the shrub and dispose of in trash. If you choose you can prune the impacted leaves off. Your buds for next years blooms are setting now so pruning may limit them in the spring. If the blight is bacterial it will likely come back next year. At that time you can determine what next steps to take. Below is a link to leaf spot and blight diseases. Towards the end of the article it touches on blight.
https://extension.umn.edu/plant-diseases/leaf-spot-diseases-trees-and-shrubs#bacterial-leaf-spots-and-blight-1156513
https://extension.umn.edu/plant-diseases/leaf-spot-diseases-trees-and-shrubs#bacterial-leaf-spots-and-blight-1156513
