I suspect something wrong with the root system.
Is it possible for rodents to dig in from the bottom ?

I dont think watering (too much or too little ) is a problem here with your 5-1-1 base medium.

I have only experience once such a wilt and death. It was under the black walnut tree.

I don't want to read this! I'm having a few issues this year with a couple of plants in the smart pots. Not sure if mine are being attacked by squirrels, which I have found evidence of. Another looked like a fungus was the culprit. I did spray with serenade and then another spray with insecticidal soap and horticultural oil. I've found small red spiders between plants. So I'm hoping there isn't too much damage. I was getting discouraged b/c with the 5-1-1 I really hoped a lot of issues would be avoided, but apparently not. I just keep removing leaves and praying. Good luck, ohiofem. Sorry I can't help! Maybe Dave or Caroline will help.
Sharon

I have only experience once such a wilt and death. It was under the black walnut tree.

You may have figured it out. The reason I grow tomatoes in containers is that my yard is surrounded by walnut trees. I try to keep any part of the leaves or trees out of my compost, and I only use a small amount of compost in my mix. But the squirrels are always trying to bury the nuts in my containers, and wind storms can blow the leaves everywhere. It may be that this particular plant was more sensitive than the others, which still look fine.

When something like this happened before, I suspected that it might have been caused by my compost having some black walnut leaves in it. My husband had added leaves to the pile without realizing how poisonous walnut juglone can be to some plants. Although I've read that composting can remove most of the juglone, I suspect some stayed in the pile that year. I'm going to stop using my own compost with any members of the nightshade family. How sad.

I doubt that nightshade poisoning would cause it to collapse overnight. My bet is it has one of the wilt diseases. A vascular disease. Cut the main stem in half and tell us what you see in the cross section.

What does this cross section tell you? I took it near the bottom of the plant. It doesn't appear to be like the photos I've seen of tomatoes with bacterial wilt. I have had it in a glass of water for about 15 minutes, and there is no sign of white ooze coming out of the cut stem. Verticillum and fusarium seem unlikely since the pot contains mostly fresh potting mix with no soil. I never use any tomato cuttings in my compost. But, I did leave about six inches of the mix from last year in the bottom of this container which is about 16 inches deep. Could this be carried over from last year?

Ohiofem, checkout this site.

http://solutionsforyourlife.ufl.edu/hot_topics/pdfs/Tomato-Diseases.pdf

There are close up photos and great information on various diseases. Actually there is even one with a cross selection like yours. Hope it helps.
Sharon

That is just too sad. I hope you figure it out.

Sharonie, I took a look at that link. In one description of how to manage Bacterial Speck, it advisedâ¦.

'Avoid growing tomatoes in summer monthsâ¦.heavy rains'

I thought that was very odd. If you don't grow tomatoes in summer months, does that mean your only alternative is to grow in the winter in a greenhouse?

Sorry about your tomato plant, Ohiofem. I hope the remainder of your plants stay healthy! And since you are growing in the 5-1-1 mix, I hope you will post photos of your plants as the season progresses.

Prairiemoon, I know i found that odd, but it must be because it was written for the hotter southern climates I guess? Which I suppose is true to some extent because I think certain months are not optimal in those climates for tomatoes.

You're probably right.

Sharon: Thanks for the link. My cross section does look similar to the photo in the section on fusarium and verticillium, but not quite that bad. I wish I could see what a healthy cross section looks like, but I'm not willing to sacrifice any of my plants to find out.

I have been researching walnut wilt and have not seen any photos of what that does to the vascular system of a tomato. I suspect it is similar. Many sources do describe the kind of sudden death I experienced. So I think the jury is still out. All these problems cannot be cured. They can only be prevented.

Here is a link that might be useful: Walnut wilt

I think you said it perked up in the late evening hours and then went totally limp again the next day. That is a classic wilt disease symptom.

Yes, the first day I noticed it, it did perk up a bit overnight after I watered it. But it collapsed early the next day and never perked up again. I have seen verticillium before, and that process took place over several days, unlike this one.

The thing is, walnut toxicity is a wilt disease just like verticillum and fusarium. The juglone poison blocks the vascular channels that transport water from the roots to the plant. I don't think it would be possible for me to know for sure what the cause is unless I could get a soil test that could distinguish between the different causes of wilt.

In any case, the solution is the same for verticillium, fusarium and walnut wilt. I've got to use all new soil mix for next year's containers.

Tomatoes are THE most sensitive plants I know. I have sprayed weed killer on some weeds and they have persisted. Now somebody sprays weed killer half a mile away and a drift of it delivers damage to tomato plants. I have planted numerous other vegetable under Black Walnut tree ( such as peppers, 4Oclock, gurds, okra, shiso, beans ...) and they survived

Juglone exists not just in soil, but also in bark, leaves, So the rain drop from its limbs and branches can carry juglone as well.
So in human terms , tomatoes are allergic to juglone among other thongs