Plant Diseases

Black Spot

Black Spot
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The characteristic black spots on infected leaves are patches of fungus, not dead tissue. The organism attacks only roses; it survives on canes and fallen leaves, then spreads easily during misty, foggy, or rainy weather. Black spot is common in regions where summer weather is warm and humid.

Target: Roses.

Damage: Roughly circular black spots with ragged yellowish borders appear on leaves. In severe cases, defoliation occurs.

Control: Fungicides, disease control

Notes: Water early in the day; avoid working among wet plants. Remove and destroy infected leaves.