Whats killing my summer squash?

Question

My summer squash have gotten grayish whitish spots, which makes the leaves wilt and then die

Answer 1

Got me too this year : ' ( That's powder mildew and it usually is caused by overhead watering (spraying) Try using a fungicide containing Sulphur. Spray it on just before the sun goes down, fungi are active at night, and switch to ground irrigation.