Midsummer Die-Off Syndrome

Here we have two Jetsetter hybrid tomato plants.  The one on the left is normal, but the one on the right decided to give up the ghost several days previously.  From the first onset of symptoms to total decrepitude takes about a week.  This syndrome, whatever it is, forces me to grow extra tomato plants to compensate for the ones that die prematurely. 

Here's a pair of Early Girl hybrids.  The one on the left is normal, and over 6 feet tall -- just the way I like it at this time of year.  The one on the right has been suffering from the syndrome for about a month.  It's still alive, but permanently stunted, and is producing tiny tomatoes that are too small to bother with.  I suspect there are several types of "syndrome" at work here.

Many people have complained about how difficult it is to grow tomatoes these days.  I remember in the early 90s we grew heroic quantities of tomatoes to sell at Farmer's Market.  Maybe the occasional plant would crap out, but I don't remember such a high percentage of my plants dying. 

One more problem:  Ideally, tomato plants would remain healthy until frost.  That way, you can pick the green tomatoes when frost is predicted, and ripen them indoors.  One year I had tomatoes till the end of January.  Every tomato plant that dies early is one that won't be providing green tomatoes at the end of growing season.