oakley: It's been plenty hot (I live in Texas!), but not damp. But, until I started pruning off the sad leaves these plants were enormous and there wasn't much space for the leaves to breathe - I imagine that could make them more susceptible to mold?
ginger2778: I think you may be right that spider mites are the culprit. I've actually seen small webs all over my swiss chard and basil recently, and couldn't figure out where they were coming from. Good eye - I couldn't even see the webs and mites in person, let alone in my not-so-high-quality photos!
Does anyone have suggestions for dealing with a very, very bad spider mite infestation? I see a few options here, but I'm not sure where to start:
https://www.planetnatural.com/pest-p...-mite-control/