Do you live in a warm, dry climate? Then you might want to keep an eye out for powdery mildew if you’re growing your own pumpkins.
Powdery mildew is most commonly found on the upper sides of leaves and appears as white patches and spots.
According to Dona M. Crawford, a master gardener at Cornell Cooperative Extension of Ulster County, “powdery mildews are severe in warm, dry climates [because] the fungus does not need the presence of water on the leave surface for infection to occur.”
She recommends to readers of the Times Herald-Record that growing powdery mildew resistant varieties of pumpkin was the best way to avoid this problem.
You can read the rest of her advice at www.recordonline.com/archive/2006/07/28/news_community-gardencol28-07-29.html.