Seen this article in my monthly news letter thought i would share.. I am dealing with powdery mildew right now on my cucumbers I think I'm going to try this method.
Using Milk for Plant Mildews
More than 50 years ago, researchers in Canada discovered that milk sprays could help prevent powdery mildew on tomato and barley. Then the age of fungicides began, with no further published research on the milk cure until 1999. Since then, numerous small studies from around the world have validated the use of milk sprays on powdery mildew on a wide range of plants. Most recently, a spray made of 40% milk and 60% water was as effective as chemical fungicides in managing powdery mildew of pumpkins and cucumbers grown in mildew-prone Connecticut. In Australia, milk sprays have proven to be as effective as sulfur and synthetic chemicals in preventing powdery mildew on grapes. In New Zealand, milk did a top-rate job of suppressing powdery mildew in apples.
Read more here http://www.growveg.com/growblogpost.aspx?id=242