Powdery Mildew on Sugar Snap Peas and Cucumbers in San Diego

Diagnosis

White patches on peas; brown spots on cucumber leaves = powdery mildew. Sprinkler irrigation spreads spores.

Treatment

• Lime sulfur or fungicidal soap (e.g., Gardens Alive Soap Shield).
• Apply at first sign; repeat per label.

Prevention

• Switch to drip irrigation — keep foliage dry.
• Space plants for airflow.
• Remove infected leaves promptly.

Cucumber Harvest Timing

Pick at 4–6 inches for best crispness/flavor. Over‑mature = bitter, tough.

Resource

Soap Shield | OSU Mildew Fact Sheet