Lilac leaf problem - Ask Extension
20 yr old common lilac has many of lower leaves that are turning black and curling up.
Gets adequate light and water.
Removed couple oldest stems ...
Knowledgebase
Lilac leaf problem #877815
Asked July 18, 2024, 3:38 PM EDT
20 yr old common lilac has many of lower leaves that are turning black and curling up.
Gets adequate light and water.
Removed couple oldest stems last year and this year.
First time having any issues.
We’re gardeners but need advice
Thanks so much in advance
Anoka County Minnesota
Expert Response
It is hard to tell what is happening without a photo. Lilacs can get a number of leaf spot diseases. A few years ago there was an outbreak of pseudocercospora infections in the lilacs in our region:
https://yardandgarden.extension.iastate.edu/encyclopedia/lilac-pseudocercospora-leaf-spot
For other possibilities, look here:
https://apps.extension.umn.edu/garden/diagnose/plant/deciduous/lilac/
https://yardandgarden.extension.iastate.edu/article/2021/08/summer-foliar-lilac-diseases
You can also send a sample to the plant disease clinic:
https://pdc.umn.edu/submit-sample
https://yardandgarden.extension.iastate.edu/encyclopedia/lilac-pseudocercospora-leaf-spot
For other possibilities, look here:
https://apps.extension.umn.edu/garden/diagnose/plant/deciduous/lilac/
https://yardandgarden.extension.iastate.edu/article/2021/08/summer-foliar-lilac-diseases
You can also send a sample to the plant disease clinic:
https://pdc.umn.edu/submit-sample
