Red spot, measles

Fungal leaf spots

Red spotPathogen

Cladosporium paeoniae.




Initial symptoms typically develop after bloom. Small, reddish, circular spots form on the foliage. Lesions may coalesce, making blotchy patches. The upper surfaces of infected leaves become dark purple; the lower surface is brown. Foliage that is infected before it is fully expanded may become slightly distorted. Infection of stems causes reddish streaks.


This fungus survives on dead plant debris and in soil. Spores are spread by rain or wind.


Remove and destroy infected plant material. Avoid overhead irrigation or carefully time irrigation to limit the duration of leaf wetness.

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The MSU IPM Program maintains this site as an access point to pest management information at MSU. The IPM Program is administered within the Department of Entomology, fueled by research from the AgBioResearch, delivered to citizens through MSU Extension, and proud to be a part of Project GREEEN.