Impatiens downy mildew

Impatiens downy mildew is caused by a fungus-like (Oomycete) organism that causes yellowing leaves, leaf loss, and death of bedding Impatiens, commonly called busy Lizzies, during wet weather and damp conditions. Attacks outdoors are most likely in summer, but could develop in spring in greenhouses.

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Defoliation caused by Impatiens downy mildew

Quick facts

Common name Impatiens downy mildew
Scientific name Plasmopara obducens
Plants affected Impatiens walleriana (busy Lizzies)
Main symptoms Yellow leaves, leaf and flower loss, white fungal growth
Caused by Fungus-like (Oomycete) organism
Timing Summer, or spring in greenhouses

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