Cercospora Leaf Spot
Cercospora hydrangeae Ellis & Everh
1 host plant · Fungal
Last updated
Cercospora Leaf Spot can show up on landscape plants, producing visible damage that ranges from leaf spots and discoloration to branch dieback depending on severity. Early detection gives you the best management options.
Start with sanitation: remove and dispose of affected material as you find it. Thin dense growth to improve air circulation, and redirect irrigation away from foliage. If the condition persists despite cultural adjustments, your local Extension office can help identify the pathogen and recommend targeted treatments.
Quick Reference
Agent Type
fungal
Causal Agent
Cercospora hydrangeae Ellis & Everh
Host Plants
1
Spread
rain-splash
Favorable Conditions
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Management
Vulnerability Window
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Cultural Controls
- Remove and destroy fallen leaves from under susceptible plants WSU HortSense
- Avoid overhead irrigation; use drip or soaker hoses NC State Extension
- Improve air circulation through pruning and adequate plant spacing WSU HortSense
- Apply urea to leaf litter after leaf fall to accelerate decomposition PNW Plant Disease Management Handbook
- Provide partial shade (40-60%) for susceptible hydrangeas where possible NC State Extension
Regional Notes
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Host Plants (1)
Sources & References
Primary: NC State Extension
- LSU AgCenter - Cercospora Leaf Spot on Hydrangea
- UMass Extension - Hort Notes 2020 Vol. 31:3
- Arkansas Extension FSA-7570 - Cercospora Leaf Spot of Hydrangea
- PNW Plant Disease Management Handbook
- Mol. Plant Pathol. 21(8):1007-1020, 2020 (DOI: 10.1111/mpp.12937) - Cercospora beticola: The intoxicating lifestyle
- Wikipedia - Cercospora hydrangeae taxonomy
Data Maturity Structured Multiple sources. Expert review underway.