How old are the plants?

Sterilizing seedling cells is generally done to prevent damping-off. If you managed to get them to transplant size without trouble, that wasn't your problem.

What have you fed them with, if anything?

--Alison

Hi Alison,

I did get them to transplant size, but it was a struggle. The unseasonably cold weather here just stopped them in their tracks and they stayed unusually small for a long time. And, frankly, they didn't look all that hardy when I planted them. But then they seemed to rally, for awhile at least. Some of the fruit on the plants that are worse off have browned and turned kind of leathery-looking.
I fed them Kelloggs tomato food (7-12-7) a couple of times.

OK, I just went outside to check something and picked a red cherry (Chelsea) that had ripened to taste. And it was so acidic it burnt my tongue a little. That has NEVER happened before.

There's definitely a water-transport issue going on here. Is the soil moist in both the containers and the ground? (Odder things have happened.)

Grab one of the poorest ones and pull it, then have a look at the roots and lower stem. Look for nubbles along the roots or cankers on the stem.

Then take a sharp knife and slice the stem down to the pith right at the soil line. You're looking for brown or black coloration either in the wood or in the pith, hollow stems, or anything else that doesn't look like fresh green healthy plant.

Also check the brown tops. Is it kind of a purplish-brown, or black, or real dirt-brown? Are the new leaves distorted at all?

Let me know if you find anything; I'll make a point to check back here regularly.

--Alison

There's definitely a water-transport issue going on here. Is the soil moist in both the containers and the ground?

Yes

Grab one of the poorest ones and pull it, then have a look at the roots and lower stem. Look for nubbles along the roots or cankers on the stem.

no nubbles or cankers

Then take a sharp knife and slice the stem down to the pith right at the soil line. You're looking for brown or black coloration either in the wood or in the pith, hollow stems, or anything else that doesn't look like fresh green healthy plant.

all looks green from the inside. The problems appear to go from the outside in.

Also check the brown tops. Is it kind of a purplish-brown, or black, or real dirt-brown? Are the new leaves distorted at all?

New leaves look absolutely healthy. When I put on my strongest glasses (I have several different pairs from different eye exams over the years) I saw that there appeared to be very tiny holes being made in the leaves that were browning, but not yet crispy. Then I saw tiny, tiny green insects. So would they be the culprets or are they just taking advantage of a sick plant?

I feel lousy about this. I usually stand guard over my plants and check them several times every day. But we've had to be out of town a lot these past few months.

Thank you for your help.

Very tiny holes could be flea beetle damage... I can't think of any tiny green insects offhand that chew on tomato leaves.

Thrips can cause scraping damage (which isn't exactly a hole) where they take the surface off of one side of the leaf... the other side is intact, but turns brown from the damage. A lot of thrip activity causes skeletonizing, where parts of the leaf turn papery-white. A small amount just causes small specks of light brown.

Example of thrip damage on tomatoes

At least the new foliage is coming out all right, which suggests they may be able to grow out of it. If it isn't a vascular issue, normal watering and a little food should help them out... If it is thrips, you can spray insecticidal soap on them anytime you see them, and that should reduce their numbers to something reasonable.

--Alison
who is just getting off of a nutty week