Milk is a useful fungicide in the garden, and is more effective than standard chemical brands.
Researchers believe the potassium phosphate in milk boosts a plant's immune system to fight the fungi.
Where most organic gardeners use a baking soda, soap and oil solution, milk may be substituted to combat the unwanted fungus.
Preparing a Milk Solution and Spraying Schedule
The correct dilution and spraying schedule for garden plants depends on the situation and takes some trial and error.
A milk fungicide solution can range from 1 part milk to 9 parts water, to a strong, milk-only solution. A 1:1 dilution may work for a week, but a 1:8 solution requires spraying every 3 or 4 days.
Skim milk may work better than whole milk, as the higher fat milk may clog a sprayer; even reconstituted powdered milk works.
Uses for Milk Fungicide
Milk was originally used in the garden to treat powdery mildew on squash plants. It is now also commonly used on flowers such as rudebekia (Black-eyed Susans) and Begonias to cure powdery mildew.
Milk has also been used to cure Botrytis on a Cyclamen houseplant. This was applied full strength every morning (leftover breakfast milk). Rotten leaves were picked away and the plant pulled through with no more Botrytis.
Black spots and rust on roses can be controlled but not cured with milk. Fortunately, milk can prevent the spread of these fungi to other plants and new leaves. This can be very useful when bringing home a plant from the nursery and finding a black spot.
The copyright of the article Milk as a Garden Fungicide for Powdery Mildew, Botrytis, and Black Spots in Organic Gardening is owned by Deborah Turton. Permission to republish Milk as a Garden Fungicide for Powdery Mildew, Botrytis, and Black Spots in print or online must be granted by the author in writing.
For example, it's known that milk has anti-fungal properties and is
used around the world to control powdery mildew on squash and melons. Farmers in Brazil and New Zealand, in particular, have used a mixture of 9 parts water and 1 part milk sprayed on plants to prevent this disease from getting started. It seems there are certain amino acids and salts in milk that control this fungal disease. Farmers in these countries get up to 90% control of powdery mildew with milk sprays. While raw milk seems best, farmers in New Zealand have used skim milk with good success.
Not only can milk prevent diseases, it's a disinfectant. Researchers at Ohio State University have found that
dipping pruners in milk to disinfect them works just as well as dipping in the usual bleach solution. Recently conducted trials resulted in zero transmission of tobacco mosaic virus from infected to non-infected petunia plants when pruning was done with tools disinfected by either bleach (1:10 dilution) or non-fat dry milk mixed with water. Plus, there's less corrosion on the pruners and skin irritation for the gardener when using milk. They used a non-fat dried milk solution, but perhaps regular milk will do too!.
So tip a glass of milk back for your body and your garden. It's more than a natural.