Here Is What You Will Need:
1. Clean spray bottle
2. Fill it with 40% milk and 60% water
3. You also need the sun to make this work.
Get outside on a warm sunny day and spray the affected areas. Be sure that you spray the underside of the leaves as well.
Allow the milk mixture to fully dry in the hot sun. This is a very important part of to making this work. The sun bakes the proteins into the leaf and kills off the unwanted mold or mildew.
BAKING SODA (sodium bicarbonate)
This is possibly the best known of the home-made, organic solutions for powdery mildew. Although studies indicate that baking soda alone is not all that effective, when combined with horticultural grade or dormant oil and liquid soap, efficacy is very good if applied in the early stages or before an outbreak occurs.
Mix one tablespoon of baking soda with a teaspoon of dormant oil and one teaspoon of insecticidal or liquid soap (not detergent) to a gallon of water. Spray on plants every one to two weeks.