Sounds like powdery mildew. There are many sites with pictures that you can find using google just to be sure. If you feel it is powdery mildew you need a fungicide (I use Daconil 2787). If you don't want to use chemicals you can simply remove diseased leaves and be sure not to let any of the leaves stay wet overnight by watering in the morning.

Thank you! Unfortunately since my post, the leaves no longer have the white substance on them...mainly because they are all just about yellow and falling off. I would say, "LOL!" but it's really not "LOL" is it? :)

We've had record highs this past week, hitting over the 100 degree mark and well over the 100 degree mark in heat index. My whole garden, with the exception of hot peppers, looks as if it is frying. I've been watering on our days but I guess with the extreme heat and heat index and even when watering in the morning, it just evaporates before the roots get any to drink.

Again, thank you for your response. I will certainly keep the fungicide in mind...didn't know what would be a good one...for next year.

Beverly