Here are my two plants. They've been doing well for the entire time:
Then right after a heat wave it started showing wilted leaves, so I thought it needed more water (many of the plants showed some stress after that), Extra watering perked them all up except this one. On further examination I see that things are not looking good at all. It's dying from the root up and there are bumps all over the "trunk."
As I feared this is bad. Southern Blight is what matches the description:
http://gardening.about.com/od/vegetablepatch/a/TomatoProblems.htm
Southern Blight is a disease that can hang out in the soil and comes out when it's hot and wet. (Drat.)
There are similar distressing photos here:
http://aggie-horticulture.tamu.edu/publications/tomatoproblemsolver/root/south_blight.html
and here:
http://www.lsuagcenter.com/en/our_offices/departments/Plant_Pathology_Crop_Physiology/Plant_Disease_Clinic/Disease_Image_Gallery/Herbs_Vegetables/Tomatoes/Tomato+Southern+Blight.htm
This site:
http://www.thegardenhelper.com/blight1.htm
says I need to remove the plant and burn it (good luck with that in my city), and don't compost it. My recycling company uses a high temperature composting method that you can even put rotting meat into, so I don't think composting is a problem.
Here's one novel solution:
http://gardeningtoybox.bloghi.com/2009/01/20/how-to-get-rid-of-tomato-blight.html
But I don't think I need to do that. I have complete control over the soil in that planter and had completely changed it out this year. My planting mix is a simplification of Martha Stewart's (make fun of her all you like, but she knows her stuff)
http://www.marthastewart.com/article/all-purpose-soil-recipe?autonomy_kw=soil&rsc=header_3
I notice that her mix keeps changing, bit by bit - didn't used to have bonemeal or charcol.
The dirt is actually optional and I don't use it as it's too much of an unknown.
It used to be: peat moss, compost: sand, dirt (optional), vericulte and perlite
I'm a little suspicious of soil with pure white things in it (perlite) so for a while I haven't used it or vermiculite. Being lazy this year, I didn't add sand in and only used peatmoss and organic compost (chicken shit actually). Now it would be easy to suspect the virus hanging out in the poulet merde (the google spell checker must know french though I don't know how to turn it on) but I think the fatal mistake was not having enough things in the soil that didn't retain water (sand, perlite, even gravel) - apologies for the double negative, so even though it was on a drip system it was still retaining too much water and it would get occasional hand watering as well.
So depending on how much work I want to do today I may be able to make a difference here.
First take the ill plant out and put it in a separate planter - it's probably doomed, but I can give it a hospice bed if it's quarantined and not sharing soil. For the healthy-appearing plant it would really help it to get sand in its soil, but I'm not sure how to do that without traumatizing it. With the ill plant gone it might be able to dry out on its own. I'll have to go see how difficult this is going to be. It's a bummer as I'm so proud of the elaborate tomato cages I created this year with bamboo stakes and tie wraps but I can always do it again.
[time passes]
And that's exactly what I did. The ill plant is in a large pot that I had sitting around waiting for another job besides holding agility PVC. I lined the bottom with play sand which I had left over from a stepping stone project. Why I didn't use it in the soil mix escapes me, unless I did and just didn't use enough of it. Put the sick plant in and filled in the rest with sandy Alameda dirt which I usually never do as these houses didn't have trash service for a long time so all sorts of rubbish is literally in it (though the plants I put in the ground have done well - what does that mean?
The remaining plant I aerated some with a pole and poured a bunch of sand all over it and tried to work it in also leaving the hole where the other one was mostly open. There is signs of blight on the remaining one's tomatoes so all may be lost, but I'll give it my best shot. I don't know if my Farm Agent grandfather woutl be proud or appalled. Farm people take the heavy handed approach and quickly. Both plants would have been destroyed immediately and the soil scattered to dry or let fallow for a couple of years. But I am a not a farmer, but a namby pamby home organic gardener (that would completely puzzle him as he passed away before any of us could spell organic.) Maybe I should talk to one of my cousins who did a stint as an organic farmer.