Powdery Mildew on Squash

Alright y'all... the dreaded powdery mildew is upon my pumpkins & squash. How do I get rid of this naturally? As you can see, my chickens nibble the leaves through the fence, so it's gotta be something safe for them. Also, is it normal for so many pumpkin blossoms to die off like this or am I doing something wrong? I water about every other day at this point in their growth and they were planted…