I realize it is Verticillium and Fusarium now. So much for my spelling, but another note I wanted to add is the leaves don't seem to ever turn yellow or get brown blotches, they just turn a dark green, then brown and dried.

It looks a lot like what I get with mites. Are any of the leaves showing white speckling, especially the ones near the bottom? Turn over some of the lower, still living leaves and look closely at the underside, maybe with a magnifying glass; look for light webbing and little crawling specks, smaller than the head of a pin. Heavier infestations have quite visible webbing on stems and leaves, with tiny mites crawling over it.

Mites move in on stressed plants in dry, dusty, warm conditions. Even once the plants are watered and happy again, if mites have gotten a foothold they're really hard to stop. Twospotted spider mites are most common, though I have the reddish-colored Pacific spider mite here in the East Bay; either one will cause russeting of the branches, leaf die-off, and plant decline.

Light "summer" oils are the usual miticide of choice, as standard pesticides only encourage them; however, oils can burn plants in temperatures over 85, which is weather mites love. It's a very tricky situation, one which I battle every year.

Your best recourse for mites is to feed the plants a heavy dose of balanced fertilizer now, keep the soil moist, keep humidity up as much as possible -- washing down the leaves in the late morning to early afternoon helps -- and spray a product labeled for mites if you get a few days of cool weather. The strategy is to get the plants to outgrow the mite infestation while removing as many of the conditions the mites love (hot, dry, dusty) as possible.

If you see no sign of mites, please let us know... but your picture and description don't fit Fusarium, Verticillium, any of the leaf diseases like early or late blight, or any of the bacterial or viral diseases. Continuing to die after they've been watered (especially from the bottom up) argues against it just being lack of water. The best bet I have is mites.

--Alison

If it was either Verticillium or Fusarium, I suspect your plants should be dead by now.

Can't diagnose on the basis of the long distance shots because too little detail about the affected parts.