Peony Red Spot

Peony red spot affects peony species in the Puget Sound region with characteristic red spots on foliage. Remove fallen leaves and debris to reduce overwintering inoculum. Avoid overhead watering which promotes fungal spore spread. Prune to improve air circulation around plants. Fungicide applications may be needed during favorable infection periods in spring. These leaf-spotting diseases are most active in cool, wet conditions. Remove infected foliage and improve air circulation.

Leaf spot and blotch diseases are primarily cosmetic on established plants, though repeated years of heavy infection can weaken them. Rake up and remove fallen leaves to reduce the spore load going into the next season. Avoid overhead watering that splashes spores from the ground onto lower leaves. If the problem is severe, protective fungicide sprays during spring leaf emergence can help, but sanitation does more than chemistry for most leaf spots.