Red spot (Measles) of Peony

Pathogen: Cladosporium paeoniae

Hosts: Paeonia

Symptoms: 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 a dark purple color, while the lower surface is brown. Foliage that is infected before it is fully expanded may become slightly distorted. Infection of stems causes reddish streaks.

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

Management: Remove and destroy infected plant material. Avoid overhead irrigation or carefully time irrigation such that the duration of leaf wetness is minimized.

Peony plants infected with red spot
Peony plants infected with red spot (Cladosporium paeoniae)
Close-up of leaf spots
Close-up of leaf spots
Red spot infected peony flower
Red spot infected peony flower

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