Tomato leaves curling

Question: Hi, I have had this problem with my tomatoes for weeks.  The leaves are curling in on themselves.  I thought it might be too much water so I stopped watering for about 3 days. They are in the same shape and looking very poorly,  I put new soil on the bed this spring. It was a 50/50 mixture from a local yard and garden. I had the soil tested and it showed that it was low in N.  Boron was also low. This was a top dressing of about 6 inches. I'm afraid I will lose my whole crop this year. What are your suggestions? Your help/suggestions will be greatly appreciated. Thanks, Mary

responder: An Ask Extension Expert Replied July 08, 2024, 11:53 AM EDT
response: Hi Mary, There are a couple of possibilities that resemble the closeup photo with the curled leaves. My first thought is accidental exposure to an herbicide, such as 2,4,D--tomatoes are very sensitive to it and it will be a very visible effect in the leaves twisting.  Pesticides like 2,4 D ester are used to control broadleaf weeds and in many cases are used when glyphosate is no longer effective.  2,4,D can volatize, especially on hot days and by many accounts  is  highly prone to drift via spray droplets, vapor or gas on air currents.  It could have originated from an application on weeds several feet away or a few miles depending on the  atmospheric conditions.  Depending on where the soil you used and if it was mixed with manures for enrichment, there can be herbicides that pass through grazing animals into manure that can damage plants.  My understanding is that Maryland doesn't allow this herbicide spraying of hay fields. The effect is very severs twisting and thickening of leaves and stems. From the one picture, I don't see that level of severity.  Broad mites can cause curling leaves and attack peppers too (same family),  but they will also cause a bronzing effect is you have a bad infestation.  PLus, it seems to be more often high tunnel growers seeing this in Maryland.  Do any other plants in the garden also show unusual growth habits (twisted, dwarfed)  or do you only have tomatoes? If you had closeups of the lower parts of the tomato plants stems and older leaves that might reveal more. At this time though, , gut level response is that it is herbicide which will set plants back, weakening them and have less than a great harvest.

responder: The Question Asker Replied July 08, 2024, 5:14 PM EDT
response: Thank you for your quick response. I have not ussed any pesticides on the tomato plants except seven dust (once).I had put a weed and feed on my grass on the other side of the yard in the early spring - I have a 1 acre lot. There is no bronzing on the leaves. I have tomatoes in a different garden and they are doing the same curling.I have lost a few pepper plants in a bed adjacent to the tomatoes. I will send you some photos of the lower stems and one of the pepper that is dieing.  Well, I’m not so good at putting pictures in my message (4 of the same one lol)  but it will hopefully give you  an idea of my problem. I made a few raised beds this spring with  peppers & broccoli with the same 50/50 mix and they are doing fine.Thanks   On Jul 8, 2024, at 11:53 AM, Ask Extension <<personal data hidden>> wrote:

responder: An Ask Extension Expert Replied July 09, 2024, 8:54 AM EDT
response: So, looking at your lower leaves and stems I see basically yellowing or dried out leaves. Neither the leaves nor the majority of the vines seem to have any leaf spot disease. I would clips off all the already dead and yellowed portions anyway especially those close to the soil. The only lower section of concern is in the picture where there are brown blotches on the stems of a dying side shoot (4th photo) and under that on the main stem. If that is affecting the interior of that main tomato stem (pith necrosis)  that may be a contributor to the poor performance. But I would expect to see that on more of the failing plants if it is a factor in all of these tomatoes. If you don't see that elsewhere. probably not the culprit. Your tomatoes should be kept moist 6-8 inches down in the soil. I don't see many of the little rootlets forming on your stems (those bumps can produce tiny roots if the humidity is high under the plant from being watered well. This tells me that your plants are very dry most of the time even after being watered. Part of that is excessive heat we've been experiencing day after day. Your tomatoes and peppers suffer when temps are in the 90's and have a hard time keeping up with water needs. They need more water since they quickly use up what is in the soil to maintain themselves.  Sometimes people will erect shade cloth structures over peppers and tomatoes to protect from the effects of these sun filled heat waves.  As far as any potential herbicide potential damage, I tried to explain that it is not necessarily anything you personally did. It could be a neighbor or a farm applying weed killer which vaporized and happened to land on some of your patch of tomatoes. I'm not certain that is the issue here--just saying  that leaf curl can occur from that. Long and short--try grooming the plants of the dead stuff and give them deep handwatering and check to make sure that the soil is staying moist to that recommended depth above. Also monitor for brown areas on main vines to see if more appear or become enlarged in that one in the photo.

responder: The Question Asker Replied July 09, 2024, 9:02 PM EDT
response: Thank you for your help. I will start watering more and put up shade cloth to help protect them from the sun.  On Jul 9, 2024, at 8:54 AM, Ask Extension <<personal data hidden>> wrote: