It's hard to tell at this stage what it might be. Could it be physical damage from the repotting process?

I would continue to monitor carefully and take photos of any new lesions/discoloration/leaf shape changes on the foliage before pruning it off. Post those photos here.

As for the fruit setting situation, the plant may just be adjusting to its new pot and taking a break to form some new roots. It may also benefit from some manual assistance with pollination with the recent fluctuating temps. Flick the new flowers a few times to dislodge the pollen and help it fall down into the anther cone. Or if you have an electric toothbrush or a tuning fork, touch it to the "knuckle" behind the flower briefly to vibrate the pollen loose like a bumble bee would.

Also--you're applying fungicide? With a lot of rain and sudden cooler temps, some diseases may be ramping up. It's possible the lesions are some grey mold, or it's possible I see an early blight lesion in one of the pics, but it's too early to tell. When in doubt, spray.

Hi there! Thanks so much for your reply!

I am not all applying fungicide. When I left it looked like it had a thrips infestation and was looking for Spinosad but was unable to find any. There is some additional thrips damage since I left but I just don't know what to buy to get rid of them. I'm new to tomato growing so have no idea what fungicide +/- insecticide to use that's available in Canada (preferably in stores so I can get spraying ASAP). What would you recommend?

Now that it's morning I've been able to get some better pictures of the damage. Some of the leaves are curling, some look a little yellow, and some have white/silver areas but the leaves seem generally improved compared to when I got it.

I spray fungicide regularly from plant-out here. EB (early blight), septoria, and bacterial speck are just regulars around here, and fungicides available to the home grower are best as preventatives. And even the, they're not 100% but can often delay disease onset, which really makes all the difference. But they can help slow down the advance of existing infections, too.

You're not seeing brown/bronze spotting on leaves, I hope? Because if so, I'd worry that the thrips had given the plant TSWV. They can look like this or like this or even something in-between. They don't look like what I'm seeing on the leaves in your photos, though the stem lesions look similar to TSWV stem lesions (but so do a lot of things, so don't panic yet!) but you said you've been trimming off affected leaves, so I don't know what you've trimmed off.

As it is, what I'm seeing in your photos looks more like the usual culprits. Onset of EB, maybe, bacterial speck is another possibility. Could be grey mold. It's still vague enough that it's hard to tell if it even is a disease.

I recommend copper, as that's pretty broad-spectrum and covers most of the usual diseases. There are organic copper formulas as well as non-organic. Not sure of the brands you have up there, but down here, Bonide, Southern Ag, Monterey, etc. usually have organic copper. Just spray weekly, adjusting for rain (sometimes I'll wait until forecasted rain is past before spraying, even if it's been a week, sometimes I'll just re-spray afterwards if I get surprised by rain). And keep pruning bad foliage off.

Chlorathonil is more effective than copper, but it's not organic, although it has a decent safety record. Brand names I know of are Daconil and Bravo.

There are biological options like Bacillus subtilis (Serenade around here), Bacillus amyloliquifaciens (a number of different brands), Streptomyces lydicus (Actinovate, etc.). I like to use those, but they're best used as preventatives and less effective once disease sets in. I usually start out the season with Serenade (although this year, I'm trialing B. amyloliquifaciens, too), and then start alternating between copper and Serenade later in the season, getting more aggressive with copper use as signs of disease show up.

If it turns out to be TSWV, unfortunately there's little hope for the plant. But the fungal/bacterial "usual culprits" are usually slow-moving, and spraying and pruning can help them move even more slowly, so you can keep plants alive and producing for a while, often until frost.

I got a copper spray today but am a bit unclear about how to apply. It's a powder and it recommends 1.25 teaspoon/10m. I just want to spray on my 4 plants that are each in a 16" pot. How much would you mix up? Do you spray leaves, stalks, and fruit? It says it's poisonous...so I'm a bit concerned about getting it on the fruit?

It's OK to get it on fruit, as it will wash off easily. It's not systemic, so it doesn't get inside the plant and contaminate it or anything. Just wash the fruit before you eat it.

Yes, I spray everything--leaves both top and underside, stems, flowers, etc.

If the instructions are unclear, contact the manufacturer. What's the brand?

The deed is done! Sprayed it all! It said for tomatoes 1.25 tsps of powder for 1 litre of water to be used over 10m2. I just used enough to spray all four plants. Any idea how to safely dispose of the remainder of the mixed copper spray?

Yes, you just need to spray enough so that all plant surfaces are thoroughly wet.

As for disposal, follow your local laws. Eventually you get pretty good at knowing how to mix up just enough for what you need. But if I had a significant amount left over, I'd put it in a bottle and then take it when convenient to my municipal hazardous waste drop off site. If I only have a little bit left over, I'll usually just apply it to some of my ornamentals or herbs that are prone to various mildews.

My plant has been doing wonderful thanks to all the suggestions, however recently it developed this stuff on a few upper leaves. I spread with copper 2 weeks ago - should I spray again? It's still producing tons of fruit but it's got some brown, dried up leaves.

You're not seeing any discoloration, distortion or strange marks on green fruit, especially newer fruit?

The new fruit near it look like they have blossom end rot?

Some other leaves on the plant look like this

OK, that looks like nutrient deficiency, in addition to maybe a touch of something fungal. The occasional BER on container plants is nothing unusual, but a nutrient deficiency can aggravate that.

I spray plants about weekly, so once every two weeks may be too much time between fungicide applications. Remember to re-spray if rain may have washed off the previous application. I usually watch the weather forecast, and if rain is due in the 10-day forecast, I time spraying for after it's over.

You say you're fertilizing with MG. Is that the general plant food? If so, that will have lots of NPK but perhaps not enough of the minerals that tomatoes need. MG has a tomato formula which will have the calcium and magnesium that tomatoes require. Or you can use any liquid fertilizer specifically for tomatoes or fruiting veg.

The miracle grow I've been using is "tomato plant food" and I add Roland's to my soil on occasion. I'll send a picture with the details.

I have slowed down my fertilization given what I had read that fertilizing can aggrevate BER.

Both deficiency and excess can aggravate BER. Too much nitrogen, specifically, aggravates BER because the vegetative growth becomes too vigorous, which shunts nutrients away from developing fruit. If your plants are flowering and fruiting well, they're unlikely to be suffering from excess N, especially in a container.

Also, BER just happens sometimes in containers. The environment just has a lot of moisture fluctuation. Regular watering helps, but it also washes out nutrients quickly.

For MG tomato, I'd fertilize at 1/4 of recommended strength every 3 waterings or so, depending on how the plant is doing.

Perfect! I'm going to try that. I've mulched them all with newspaper and tinfoil to try to retain more moisture and to battle thrips.

Are the affected leaves curling? Can you post a pic of the top of the plant?

Some were dried and curling. The top of the plant now looks like very light coloured leaves with purple on the stalk

OK, that is definitely pretty serious nutrient deficiency.

I was worried because leaf bronzing, dark streaks on stems, and curling starting on the newest leaves is a possible symptom of TSWV. And I know you've had ongoing issues with thrips.

But necrotic spots can also be a symptom of serious nutrient deficiency.

If you notice any distortion, stunting, or ringspots/marbling on fruit (brown or white on green fruit, yellow or brown on red fruit) or the leaf lesions take on a marbled or leopard spot appearance, that will be fairly diagnostic for TSWV, and you'd have to bag the plant and throw it away.

But so far, your fruit looks pristine aside from a little BER, which could be caused by nutrient deficiencies, and those leaves in your last pic look pretty characteristic for mag and phos deficiency at least, probably also micronutrients. And though I see dark streaks on stems in your previous photos, I don't see any virus-like ringspot/marbling patterns in the lesions on the leaves.

TSWV can be frustrating to diagnose because there are different strains that present differently, and it looks different on different varieties and depending on how mature the plant is when it contracts the virus.

I'd give the plant a good, strong feeding right now, say at about 1/2 strength, then another at 1/2 strength in a few days, then do the 1/4 strength feedings every few waterings to maintain plant health. If the plant continues to decline despite this, document the symptoms and report back or contact your local county extension office for diagnosis.

I have wondered about TSWV. Originally I had it in close proximity to another plant that I was "quarantining". That plant has since really flourished, and yesteday I moved it into close proximity to my healthy plants. It shows no sign of TSWV. I'm just wondering if that was a bad idea...could it still contaminate my healthier plants? Also, the plant that may or may not have TSWV - can I keep growing it as long as it's separated? It has tons of fruit that are right on the cusp of rippening.

Went to water today and did find one or two curled up leaves and brown on stalk has progressed quite a bit.

Went to water today and did find one or two curled up leaves and brown on stalk has progressed quite a bit.

Proximity is obviously a factor, but a lot of times, people see the symptoms a while after the disease was actually passed to the plant and thrips are gone. You often see one or two plants here and there in a field affected while neighboring plants are fine.

I would keep it separated from other plants and monitor carefully. Right now, it's far more likely to be nutrient deficiency. It's just that TSWV is possible, so I think alertness is called for. Without more definitive symptoms, I'd keep a plant that was continuing to produce well that has a high likelihood of just needing more fertilizer. I would at least see how it responds to a good feeding and whether new growth after feeding looks healthy. In an in-ground situation where the plant couldn't be distanced from its neighbors, maybe the calculation would be different.

Others may disagree, of course, as TSWV does have a wide host range, so it's not just tomatoes that are at risk. I can only tell you what I'd do in your shoes.

Also, Early Blight can also look like that sometimes. And I wouldn't pull a plant producing well for Early Blight, which can hopefully be managed with pruning and spraying.

If it were a virus, the lesions would happen first on the very newest leaves. The damage would be very top-town. It looks to me like what's happening isn't on the very newest leaves, although not on the oldest leaves, either. Although EB tends to start at the lowest leaves, it doesn't always, and the stem spots you reported before could be EB as well.

Unfortunately, disease diagnosis is never 100%, even less so over the Internet. I hope I've been able to give you an idea of how to gauge your risk, though.

THANK YOU SO MUCH. I'm so appreciative of all your help.

So I sprayed copper again the other day on my diseased plant and had leftovers so prophylactically sprayed my healthy plants a bit too. Now one of healthy plants has spotted leaves - could it be edema? Or a reaction to the copper?

Not edema. Did you spray on a sunny day?

On closer look, that seems like pest damage. Probably flea beetles. Is the damage mostly toward the bottom of the plant? Also, is it all over the plant or just on some areas?

I would also check for tiny baby caterpillars on the undersides of leaves, especially leaves near the damaged ones.

The damage is actually mostly on the top! Really just at the top in fact. Not getting any work. I inspected and found no pests...maybe I didn't look hard enough?

If it's only in the top, it might be from burn from spraying on a sunny day. It doesn't look like any fungus. I think it's more likely to be from a mobile pest like leafhoppers, beetles, etc.

The plot thickens. Plant looks good except for some necrosis/purple veins/stems of the new growth. Tomato is spotted. TSWV? Also, can I still eat it?

You can eat any tomato that doesn't have active mold growing in it. You could probably get away with eating those, too, as long as you don't eat huge quantities of them, depending on the species/strain of mold, but who would want to?

That tomato could be atypical TSWV markings, but it looks more like blotchy ripening to me. Can you post a pic of the new foliage with problems?