Extension > Garden > Diagnose a problem > What's wrong with my plant? > Deciduous > Lilac > Spots or blotches on leaves
Lilac > Leaves > Spots or blotches on leaves
1 of 3
Powdery mildew
Microsphaera syringae
- Leaves have dry, grayish white spots, blotches or are completely covered with white fungal growth
- Leaves appear dusted with flour
- New leaves may become distorted
- More information on Powdery mildew
2 of 3
- - CLICK PHOTOS TO ENLARGE -
Bacterial Blight
Pseudomonas syringae pv. syringae
- Dark brown leaf spots with yellow halos, center of spot may crack and fall out
- Leaves on the end of the branch turn completely brown to black
- Flower buds are limp and black
- Infected buds are black and will not open
- Common with cool wet spring weather
- More information on Bacterial Blight
3 of 3
- - CLICK PHOTOS TO ENLARGE -
Ascochyta Blight
Ascochyta syringae
- Current year's shoots and flower stalks are wilted, brown and often form shepherd's crook
- The stem of infected shoots is tan, shrunken and peppered with gray to pale orange spore producing structures
- Water soaked, olive colored blotches appear on leaves in late summer; coalesce until entire leaf is brown
- Leaf blotches may grow together until entire leaf is brown
- More information on Ascochyta Blight
