90% confidence
Based on 20,000+ analyzed cases
Fungal Leaf Spots on hydrangea
What's Happening
Cercospora leaf spot (Cercospora hydrangeae) thrives in warm, humid environments with poor air circulation and prolonged leaf wetness.
How to Fix It
- 1
Remove and destroy all infected leaves to reduce spore load.
- 2
Assess dormancy timeline: if imminent, prune severely; otherwise, apply targeted fungicide like chlorothalonil.
- 3
Improve cultural practices by enhancing airflow and watering at soil level.
How to Prevent It
Optimize environment with better spacing for airflow, reduce overhead watering, and apply preventive fungicide in spring.
Related Problems
Frequently Asked Questions
What causes fungal leaf spots on my plant?
Cercospora leaf spot (Cercospora hydrangeae) thrives in warm, humid environments with poor air circulation and prolonged leaf wetness.
How do I fix fungal leaf spots?
Remove and destroy all infected leaves to reduce spore load.. Assess dormancy timeline: if imminent, prune severely; otherwise, apply targeted fungicide like chlorothalonil..
How do I prevent fungal leaf spots from happening again?
Optimize environment with better spacing for airflow, reduce overhead watering, and apply preventive fungicide in spring.