Spray Your Plants With Milk?

I know it seems strange, but read on...

If you've ever seen a plant with its leaves dusted with a talcum-powder-like substance, you've seen powdery mildew. Another sure-fire sign of powdery mildew attack is when the new leaves curl up tight, sometimes all the way back to the shoot.

Prevention

Give your plants plenty of breathing room. Thin your perennial garden or trim back overly tall plants that are shading or falling into others.

Put each plant in as much sun as its species will allow.
Water underneath the plant whenever possible, keeping moisture off the leaves. After a rainstorm, go give your plants a little shake to put raindrops where they belong: on the ground.
Keep an eye on air circulation patterns, which are affected by surrounding objects (trees, ridges, houses, etc.). Either move your garden or remove the object blocking the air.
Keep it clean! Remove last season's mulch or stir it up. Rake out fallen leaves. Completely uncover plants in the spring as soon as it's safe. Cut out and remove weak plants, dead branches, and spent flowers. If you've got a really bad attack, just give up and remove the whole plant so it doesn't spread to the neighbors.

Use An Organic Spray: Milk

Powdery mildew and black spots seem to be the most common diseases that cause gardeners to reach for the spray bottle. Now, instead of reaching for a chemical fungicide, gardeners can open the fridge for an excellent fungal control: milk.

In 1999, a Brazilian scientist found that milk helped control powdery mildew on cucumbers just as effectively as a synthetic fungicide. Since the study was published, the news has traveled around the world and encouraged gardeners and farmers alike to try milk as a fungal control for a variety of diseases.

So far, there has been success reported on the use of milk to control powdery mildew on zucchini, melon, and squash. It's been tried on grapes, too, and has been effective on Black-Eyed Susan and begonia. In addition, it has also been found to be an effective control (not cure) of black spots on roses.

Any type of milk can be used from whole to skim to powdered. However, the low-fat milks have less of a chance of giving off any odor or clogging your sprayer. The recipe calls for milk to be mixed with water to a ratio of 1 part milk to 9 parts water and applied every 5-7 days.

Keep in mind that "more" is not "better" here. Use the ratio above, or you might find yourself with another interesting mold caused by the milk itself.