Answer: Without seeing the plants I can't give you a positive diagnosis but if other plants in the neighborhood are doing the same thing, I'd bet it is weather related. Your soils tend to be alkaline so sometimes an application of iron will help things green up. I use Ironite on my landscape plants and they seem to green up right away. You might try this with yours, too. But the bottom line is that if the plants are heat stressed, they can develop yellowing leaves and growth will be poor. All you can do is wait for cooler temperatures. Best wishes with your landscape.
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