What caused the turn around. Not sure. Possibly: The beginning of the rains and still lots of sun. They seem to need both. However, I think the trick is my sludgy black magic mulch.
I have been mulching the plants with the compost left over from making the organic fungicide laced with trichoderma. It is amazing stuff. Mulch, food and disease control all wrapped into one sludgy rich, and quite attractive to look at, black mulch.