"Gloria P" wrote in message
...
Paul M. Cook wrote:
Lots of dusty gray patches on many leaves. Did not notice this until
today. What is it and what can I do about it? Weather is warm and dry in
SoCal, cool nights.


Powdery mildew, fairly common on vine crops like cucumber, squash,
and pumpkins. It usually occurs near the end of the growing season.

The cure depends on how much you approve of chemicals
on your garden. A garden center should have a mildewcide.

gloria p

I've had luck with oil sprays. Neem or Canola/fish mixed oils seem to work
fairly well. YMMV - the spray won't save the badly infected plants, nor will
it stop infected leaves from dying. It's pushing the end of August and I
haven't yet seen any mildew on my squash, but it's pretty much inevitable
around here.

Humidity and overhead watering make it worse. Crowded plants also make it
worse. Dry windy conditions make it better. I can't water my squash overhead
at all, it's practically a death sentence to do so this time of year,
especially when the weather cools below 80.