I dont compost so no. 🙂

Blight was my first thought as well. But I also noticed that your plant is light green to yellow, all over. Can you tell us more about your fertilizing and watering routine?

Using pots, esp ones less than 5-10 gallon size, is marginal at best for growing large tomatoes. Using them for cherry size can work but as far as what's wrong with those plants it does appear to be a blight and/or viral related disease.

@HU-420254984 @nandina I have an issue very similar looking in western Pacific northwest. I have reused some soil from last year when I had root rot from overwatering. It also looks like a virus that is spread by pests, and looks as much like overwatering as underwatering. One thing is for sure, certain strains are more resistant to whatever it is, and I am using grow bags this year, bags that I used new soil all look great, old soil about 80% OK, old soil + pots all look the worst. Interestingly, I cannot keep pots moist for very long as per moisture meter compared to bags (esp new soil - it's very retentive). Just yesterday I took potted tomatoes down from elevation, left bagged tomatoes elevated, I am going to try mulch + compost over a soaker hose and water deeply every 3-5 days instead of every day / every other day as I had been watering them.

These are the potted ones with issues

These bagged ones mostly doing well

Before I moved the ones having the most issues. This is when I discovered it was really hard to keep the pots moist, so I moved them somewhere with slightly less direct sun and put directly on ground so don't drain so quickly.

These were actually runt throwaway tomatoes I planted 2-3 deep in totally huge half-full grow bags, just to give them a chance and they're doing the best out of all of them 😂

You need to feed those plants. Those purple leaves and the ones with purple veins are a classic sign of a phosphorus deficiency and the yellow pale leaves are screaming feed me nitrogen and potassium now!

@HU-420254984 this is what I was th5i might have, and it looks about the same as your issue. Are your plants outside where they could get bitten by some insects? https://ipm.ifas.ufl.edu/agricultural_ipm/tylcv_home_mgmt.shtml

@outpaientzero thanks for the tip. Actually, that's a big reason I took the pots down and put them straight on the ground, I think they were draining too fast and all their nutrient running right out of them.

Coincidentally, I just made a bunch of liquid bone meal out of espoma dry bone meal to use as a foliar spray. It has a lot of calcium & phosphorus, but I also have some magnesium hydrochloride I could add to it (it's extremely water soluble).

Usually hesitant to use any liquid on tomato leaves, but it's been unusually hot here this summer and I've had great luck with fish emulsion in a spray nozzle/mixer for nitrogen feeding, so I thought I'd try some of the other nutrients this way, too.

I also try to go light on the nitrogen during fruiting, so foliar spray helps moderation - the nitrogen starts working and becomes noticable within a few hours. I don't want to encourage them to spend too much energy on more vegetation.

Btw have given them all potassium via soil w/ morbloom + fish emulsion (5:1 ratio, so lighter on the nitrogen for that application) within the last week so holding off on potassium for now

Actually @Avery F I didn't even look at your pictures and was addressing the OP. But I just looked at your plants and setup and must stay it's something. If you're having a watering problem use a drip system with a fertilizer injector. I use something like it for ground planted tomatoes but I also set up two drip systems for other people growing in pots with fabulous results. They drip 24/7 with miracle grow for tomatoes in the injector bowl and the only thing they need to do is fill the bowl with fertilizer when it's empty. No splits or blossom end rot with nice healthy huge plants producing perfect tomatoes. If anyone needs a drip system it's you.

That's a neat idea. I had spray nozzle emitters on these plants along with 2L bottles buried a couple inches deep with a few really tiny holes (I want to say 5/32"?) But recently just switched the sprayers to 1/4" soaker hose behind 1GPH pressure regulating drip emitters and covered with thick layers of compost and mulch.

I am going to try some masterblend 4-18-32 w/ about 1/2-1/3 recipe calcium nitrate every two weeks through the bottles, which deliver the nutrients to the deeper roots really well, but a continuous delivery system sounds like it could be really fun. I don't always remember my schedule 😂 how do you pump the nutrient, and what kind of tubing?

Ooh, I bet I could just hook a pump in a bucket up to my soaker system ... Would have to be a big bucket though... 😂 30 18-gal pots @ 2.5 gal/pot, what's the math on that? 😂

I managed to nurse my plants back to health by putting them on the ground and feeding them a hydro mix - it says suitable for soil if used once every 2-3 weeks, but hydro mix is meant to be given to plants on a continuous basis without any nutrients in growing medium, so its nutrient profile is complete. I thought that would be helpful given that I really have no idea what nutrients might be lacking after essentially being flushed from gravity pulling the water out of the soil while they were elevated. Check them out now though!

This is the circle of bad looking tomatoes I "quarantined" by moving them out of so much direct sun and off the planks they had been elevated on. The hydro mix I used is masterblend tomato and vegetable, 4-18-38, which is the same as Greenwaytech's tomato btw. It calls to be mixed 2-1.5-2 tsp hydro mix - epsom salt - calcium nitrate per 5 gal bucket. I upped this to 3-2-3 tbsp per 5 gal for soil use and gave each plant 1 gal, washing in with a moderate amount of water, and then giving their usual 3-5 day 2.5hrs of 1gph soaker water the following day. The day pictures were taken were 2 days after treatment and 1 day after slow seeping soaker hose watering. Btw the calcium nitrate makes the effective NPK 19-18-38.

Some of the plants that did not get the hydro mix treatment are significantly yellowing, but I'm experimenting with urea + teravita sp-90 humic acid as a foliar spray on those separately. Urea is 46-0-0 so it will be interesting to see how that works out, have to be careful not to over do it - 2% dilution is max strength. Also mixed the humic acid with soil in an area where I just transplanted some radishes, about 1 tbsp per 1.5 - 2 ft, so eager to see how that goes, too. My radishes already go nuts because I hollow out where I plant them and re-fill the soil with a couple inches of vermiculite so their roots can spread out easily in a bed that is primarily clay-heavy soil (our yard's composition). We're talking golf to tennis ball sized radishes, they literally pop out of the soil they're so big, and a good number of them actually split from growing so fast (maybe need more phosphorus... Hmm)

Thank you for the comments and suggestionstigons, although I’m afraid it’s too late for this summer. I’m new at this, and tried researching but frankly, got lost in a morass of conflicting information. kevin948, is there a good all around tomato fertilizer I can use next time? I’ve also made note of the larger pot advice. I’ve been watering on the basis of checking for moisture an inch or so down in the soil which depends on the weather. It’s just now 90ish here, which is unusual and requires more frequent water with pots. I appeciate all the pointers!

I've used jobes tomato veg, Alaska fish emulsion and morbloom, blood meal, bone meal, miracle gro (organic and regular), a bunch of off-brand organic stuff from local producers, etc.

I have to say the best results I've had with any fertilizer was the masterblend tomato hydro mix, 4-18-38. You add calcium nitrate and epsom salt in a 5 gal bucket. It has everything your tomatoes need because it's developed for use in growing medium, but it worked ridiculously well for me in soil, people who were already impressed by my garden said their jaw hit the floor after I used that stuff. I personally have never seen anything like it.

Since you use W/ calcium nitrate for nitrogen, it's got a lot of calcium in it to prevent blossom end rot. You really don't need anything else. My ratio was 3 tbsp masterblend, 3 tbsp calcium nitrate, 2 tbsp epsom salt in a full 5 gal bucket, give the plants about a gallon every 4-6 weeks. For tomatoes, remove the calcium nitrate after they start developing fruit, as you don't want them to keep growing in size.

If you want to stick organic, jobes is good with bone meal, use like a cup per pot when amending soil, and stick a tbsp of bone meal in the hole when you plant (or 1/4 cup of you amend beforehand). Then give the plants a foliar spray with a hose end sprayer of 1/4 cup fish emulsion in full 32 oz sprayer (I use dial n spray) and turn it up between 4 to 8 oz per gallon. Spray it all over the leaves when there isn't too much direct sun and it'll absorb the nitrogen right through it's leaves. Most people recommend every 2 weeks, I tend to do about once a month, but if it was all I did I'd do it more often.

HU-

If you want to grow in pots next season, you might consider using varieties that are more compact. The Dwarf Project varieties were designed to grow in 5-gallon containers and there are lots to choose from. There are some compact varieties that thrive in containers.