Milk as a Remedy for Powdery Mildew

Powdery mildew has been a major blight on my garden. It almost destroyed my lovely Ribes sanguinem earlier in the year. I had to cut it way back. :( I've just been reading that milk, diluted to 1 part to 9 parts water, makes an effective fungicide spray alternative in preventing powdery mildew. Super cool. I'm going to try it!