Yeah, your triple digit streak is making news across the nation. Lucky, lucky you. ;)

It probably doesn't do them any good, but it's also possible it's Powdery Mildew. I know, sounds dumb, but it's really a soil-born fungus that spreads by air. Do a little googling on it, and see if you can find pictures to see if it looks familiar to you. I know cukes, squash, and lilac are particularly suseptible.

If that's it, at least you don't have to treat the leaves in the middle of the day. In the evening, which really isn't any better than the middle of the day, but at least you're out of straight down sun. And, since you're also in the middle of a mean drought, you won't have to repeat as often as usual. ("Repeat treatment every three weeoks or whenever it rains.")

And, yes. If you're beginning to wonder, there will be a day when Dallas goes back to cooler weather. Promise. I can't make the same guarantee about your drought, but I'm pretty sure that will end too, eventually.

need more imfo, its guessing. what size container,soil, fert, sun, etc. (pictures)