First and foremost - never put moldy leaves in your compost. The spores will survive and spread.
As for getting rid of mold on leaves, I was able to find three different organic solutions that can be sprayed directly on the plants to alleviate mold:
- Chamomile tea. Make a strong brew and let it cool first before spraying. Chamomile tea is high in sulfur and is a natural fungicide.
- Baking soda and water. Mix 1 tbsp of Baking Soda and 1 gallon of water and spray on leaves.
- Skim milk and water. Combine at a 50/50 ratio and spray on. This remedy supposedly changes the pH of the surface of the leaves, which prohibits the mold from surviving.
PS - here's a handy link http://www.ghorganics.com/page15.html with more remedies for other plant diseases (in addition to mold).
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