This is most likely a result of powdery mildew and downy mildew occurring simultaneously. Both are common fungal leaf diseases, especially in conditions with high humidity, poor air circulation, or significant temperature fluctuations.
Recommended treatment:
For small-scale planting:
Use Mr Ganick Organic Plant Acid RTU. Spray once every 3–4 days, for 3 consecutive applications.
For larger-scale planting:
Mix 40ml Mr Ganick Mildew Shield with 20L of water. Spray every 5–7 days, for 3 times in a row.
For ongoing prevention after improvement:
You can mix baking soda with water as a preventive measure. Mix 25–30g of baking soda with 20L of water, and spray every 7–10 days. If the condition worsens again, return to the first or second treatment option.
