spots on hydrangea leaves

Question

Hello – some of my hydrangeas have very spotty leaves that have turned reddish in colour. I think this is a fungus but am not sure. Would you be kind enough to let me know what this is and how should I treat it?

Also, can it pass from plant to plant if they are touching?

Many thanks, Alison Harrison.

Answer 1

Could it be Cercospora leaf spot? See link: https://extension.psu.edu/pests/plant-diseases/all-fact-sheets/hydrangea-diseases