Need ID of spreading tomato disease and advice on what to do next

First I have to ask why that bed has so little soil in it? Raised beds such as that in your picture need to be filled up to within 1-2" of the top rim.

Second, is all that red stuff some sort of cedar mulch or something? If so then that is much of your problem right there and needs to be removed. Cedar is an ornamental- flowers and bushes - mulch only. It not only harbors and encourages fungal diseases but binds up soil nitrogen just like all other wood chip mulches do.

Third, what sort of mix did you put in the bed? If it is soil (dirt, topsoil) rather than one of the many soil-less potting mixes recommended then that is another source of problems as it supports both the brown vascular wilt diseases - fusarium and verticillium.

In other words, based on the info so far, the primary issue isn't the plants but the garden bed itself and until that is fixed there is little point in replanting in it.

So could you provide much more info on the bed itself please? That will help a great deal in determining what has done in the plants.

Dave

Link to your other post on this question.

Here is a link that might be useful: Your other post of this question

[Thanks, Dave, The OP was eaten in cyberspace. It had all the extra details and i spent a considerable amount of time on it. I was so angry when I had to retype it all I forgot to include some of them in this version. The "more info" post was just supposed to be a followup comment to the OP that doesn't exist apparently.]

Anyway...

1-
The beds have a good 12" + of Viagro organic potting mix, composted cow manure and partial bale of peat moss. They are on top of a very nutritious garden bed that has been in use a few years. We have lovely top soil that I have been amending for a long time, but was tired of dealing with weeds from neighbor's yard creeping in and so we added the raised beds this spring to look nice and help delineate the beds from weedwhacker approved areas for my DH.

Transpalnts had additional Plantone and bone meal down in their holes. Have also been using fish emulsion. This is what I usually do. Our soil is very fertile, rich, and loose - dug down over 12" in the existing garden, so I did not feel the need to rush and fill the boxes to the top on the first go. I want my plants to get the nutrients from the soil beneath, plus potting mix adds up when you are renovating the whole garden with new beds. (I gave them a boost of the mychorrizal fungi (Thrive) just over a week ago, to try and pump a little more beneficial life into the mix.)

Cedar mulch was added very recently, maybe two weeks ago. After problems were developing but before I pulled anything. I usually use cypress mulch and had never experienced a problem like this in ten years of gardening here. No tomatoes in this area of garden since 2008. I usually mulch once temps are staying in the 90s week to week, which they were.

There is no mulch in the beds that have peppers, btw, as I had some summer greens with them. They were first to have any leaves drop, but as I said, they appeared as sunscald and I didn't think twice about it.

SO at any rate, I don't think I did any bad gardening except I had never heard not to use wood mulch around my plants, so I have been doing that for 10 years! I used the cedar for first time this year, but other than that all has been pretty usual for me. I can pull that away but I don't think these tomatoes are going to make it.

I don't mean to say I do everything perfect, but just have never run into all this. I did put a lot of thought into my garden planning renovation, so I would like to salvage what I can, and know what to go ahead and cull.

I am pretty sure upon the existing tomatoes are going to have to go. I went back out and cut heavier stems that are showing internal symptoms in tissue. I hate to get rid of them, but don't really want a garden hospital all summer either. That's pretty depressing. Ugh.

They are all gone now. The worst offender was a transplant of Ponderosa that was given to me at a community garden work day. Perhaps a carrier? It was very damaged inside, but had been the largest plant when I put them out back in early May.

I bagged up all the debris that I could (before I realized what was up I had placed some in a general lawn & leaf debris pile that city regularly takes from alley) and will remove the mulch to be used only around flowers etc.

I'm going to continue my neem oil spray on the nearby peppers in hopes that they just have a light case of black spot from all the heavy thunderstorms we have had.

I will replant okra in the tomato bed and maybe some sunflowers.

I found some room at the community garden and will just try a late season crop of tomatoes there.

Correction - I bagged up the mulch, too. City is picking up the lawn and leaf pile as I type. I am going to spray fungicide where it was.

Should I let the bed bake with affected soil exposed? its really hot and sunny today in the 90s. Should it get treated with Neem or other fungicide (or leave it alone)?

I'd suggest a fungicide for the pepper plants ranter than Neem. They look like Alternaia.

Soil spraying fungicides - personally I don't see how they can be effective on more that the surface but products for soil drenching are available, expensive but available. Your choice. One of those can't hurt and might help situations. Forked, sun exposed, and left to dry out well kills much of an soil fungus.

Dave

Do you mean to spray peppers with a copper fungicide? Neem oil is listed as a fungicide against alternaria. I have never had to get into heavy fungicide use before and have never used a copper spray.

I am letting the soil dry out really good. No rain in the forecast and getting hotter all week.

Thanks,
Kate