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applestar
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Tomato leaf disease or herbicide?

In two of my vegetable garden raised beds, I had a bunch of volunteer tomato seedlings come up from not quite finished compost that I used. I had been thinking of saving some and letting them grow, but today, I noticed that nearly all of them have been struck by something — here are two good representatives:

Image

Do these look like typical fungal disease to you? I’m not really seeing septoria or early blight here. But we did have some heavy rains with dip in the temperature for a few days here.

Could they be bacterial or viral? The bed on the left had tomatoes in it three years ago and had been considered due for 3rd year rotation of tomatoes, but if this is disease, I will have to re-think my plans. The bed on the right is going to have melons in it (that’s why it’s full of weeds still — they are all getting hoe’d down soon).

I’m not ruling out herbicide drift since I have seen my next door neighbor’s lawn service come around. I have taken steps to barricade the lower 24 inches of the picket fence with solid barrier, but if they hold their spray wands high (instead of to the ground like they are supposed to — a supervisor told me that in previous years) and blast around, they could easily create a dense fog that might have drifted over. I haven had the chance to speak to them yet this year — usually I make a point of talking to the lawn service people over the fence and take names if it seems necessary, as well as speaking to the neighbors.

...but it really looks like only the tomato seedlings are affected... none of the weeds.

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Gary350
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If the problem is isolated to a few leaves per plant I would pull off the leaves then wait see what happens. Some herbicide is designed to spread to the rest of the plant even if only a few leaf get herbicide on them so pull bad leaves off. Too much nitrogen and sun burn can make leaves curl up. It has been a long time since I have seen sun burn tomato leaves I'm not sure I remember what it looks like I have been using a large tree for afternoon tomato shade.

I have had my tomato plants get weird leaf problems. Sometimes problems start low near the soil then work their way up the whole plant. Sometimes a few leaves have a problem I pull them off then problem is gone. Last year I bought several variety of tomato plants 1 Jet Star plant started having curly dry leaves then 1 by 1 all 4 Jet Star plants had the same problem. Problem got worse plants never tried to produce tomatoes plants died so I pulled all 4 plants up. The problem was only on the 4 Jet Star plants none of the other 18 tomatoes had the problem. I think it is too early for your plants to have blight. You can spray full strength kitchen vinegar both sides of leaves wait 5 minutes then spray plant with garden hose water to remove vinegar I have had pretty good luck with this blight and fungus.

I have had blight problems in the past an did lots of experiments that shows calcium & baking soda 3 times every week on the soil near each plants helps prevent plants from getting blight. If plants get blight I start giving then heavy doses of baking soda I read somewhere baking soda is good to stop blight but I think it only slows it down. I have experimented and learned if I put lots of baking soda on 8 tomatoes plants and no baking soda on the other 8 plants the no baking soda plants die sooner from blight, the other plants with baking soda will survive 1 to 3 months longer. I also read copper sulfate is used for blight so I bought some I put 1 teaspoon in the soil at each plant when I plant each tomato plant. Iron is very good for blight and any fungus I put rusty nails by the hand full under each tomato plant. I also burn kitchen empty food cans in a fire to remove varnish so cans rust easy a few weeks. I water plants with rust water it seems to work good for blight. Preventive maintenance is better than waiting until plants are sick once my plants get blight I can slow it down but can never get a 100% cure.

pepperhead212
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Apple, I had some of those reddish brown spots on the lower leaves of some of my tomatoes early on, but, as you noted, it didn't seem like the usual fungal diseases on tomatoes, and it didn't hold them up at all, as far as growth. I just figured it was something related to being put out, as it seemed to be just on those leaves that would have been on when I put them out, even though I hardened them off, somewhat. I'd take a photo, but they are covered with surround, so they are white! lol I also added some aspirin to the surround spray - not sure it will help, but I figured that I'd try that, given the bad fungal problems last year, with all that rain later on.

imafan26
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Actually, it does not look like a disease. It looks like thrip damage. Western flower thrips do that kind of damage on a lot of different plants, and it is the time of year that they appear.

I could not zoom in any further, but that is my guess anyway. It is especially suspicious because most of the patches are in the soft areas of the leaf and not really near the veins.

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applestar
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Interesting! Thanks for all your comments. The one from imafan about possible thrip damage gives me a pause — I have often said I don't know what they look like. Could it be that the early heat waves brought them on somehow?

Hopefully the beneficials are also getting ready to explode into action. I will keep an eye on the ones that I might still want to keep, and try some of the suggested remedies.

imafan26
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Western flower thrips need magnification to see them, so they are usually diagnosed by the damage they cause. A heavy rain usually takes care of most of the problem. Thrips have a wide host range and anything that kills them usually hurts the predators as well. If you do treat, the treatment needs to be global. I do use 3 in 1 spray for that or Orchard Spray. Flowers will need to be disbudded at least 2 days before the sprays.

I especially have to hit the preferred hosts which are the orchids, gardenia, Jasmine, peppers, and panax.



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