White Spots & Holes on Rose Leaves: Powdery Mildew

Central NY: Rose leaves have white spots and holes. Some bushes: holes in every leaf, no buds. Others: buds with fewer holes, white spots. Given last July–August, were fine then.

White Spots = Powdery Mildew

Fungus burns leaf tissue → dead spots → holes. Favored by warm days + cool nights.

Treatment

• Organic: 1 tbsp baking soda / 2 quarts water, spray daily until spots gone.
• Chemical: Any rose fungicide labeled for powdery mildew.

Prevention

• Some varieties are prone—watch early next spring.
• Improve air circulation.
• Water at base, not overhead.

Holes are secondary—dead tissue falling out from mildew burns.