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Powdery Mildew on Potted Cherry Seedlings: Indoor Fungus Control

Diagnosis

Montmorency sour cherry seedlings (6") brought indoors for winter (N. Ontario). Leaves died with thin white powder; new growth same. = Powdery mildew.

Control

Fungicide spray (repeat per label).
OSU fact sheet: https://ohioline.osu.edu/hyg-fact/3000/3047.html — lists effective fungicides.

Why It Recurs

Indoor conditions (low air circulation, humidity fluctuations) favor mildew. Treat promptly on new growth.

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