Low leaves wilting on tomato starts

I am not new in growing tomatoes from seeds, but I never faced what I see now on many of my tomatoes. The lower leaves wilt starting on the stem and die off. Tops look healthy, though some have clear signs of edema. But the lower leaves that dying do not have that signs. This year I have several new factors in their environment - LED lights vs fluorescent lights, somewhat lower temperature - 62-65F at night, 70-75 during the day vs constant 75-78 in old environment. Also by the state they are now they should be in the greenhouse, but this year I do not have one, so they do have some sunlight through the windows(when we have sunlight, last two weeks were very gloomy) . The watering regime is regular, I don’t think I over water them. The soil mix is regular as well, 2 parts of compost, 2 parts of peat moss, 1 part of vermiculite and 1 part of perlite + Osmocote and lime at recommended rate. Some of the lower leaves started to show sign of deficiency in K(very thin light border on some leaves) and P (purplish color on some leaves ), which is very strange as they just a month and 4 days old and Osmocote should have them covered.

Any Ideas?

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Galinas, I do things very similar to your way. Lights, temps, soil mixture. Mine are out in the greenhouse now and have gone through rough times with cool, damp conditions until we had an improvement weatherwise. They responded well and look better.

Yours are ahead of mine. I now have some moved from pint into gallon pots and will do others soon. Eventually they will be in their final 7 and 17 gallon containers.

Just by looking at yours i think they may be a bit stressed from needing to be moved into larger containers. Being root bound they will show signs of it. Try moving some into bigger homes. They look like they want to really grow but have cramped feet.

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I always grow them in 1/2 gallon container and they are now just half their target size when they go in the ground, so I don’t think so. They do struggle with something, but not with the size of the pot yet.

I always cut off the lower branches anyway to reduce the spread of fungus once in the ground

Me too, but I try to figure out the fate of my tomatoes - there at least 2-3 weeks before they can go to the ground.

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What type of heat do you have ?
Maybe ethylene?

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Are you seeing edema on the leaf stems of any of the leaves affected?

@Hillbillyhort: Hmmm, our primary source of heat is pellet stove. I need to see if it emits ethylene. But it is far from the tomatoes, they are in middle of the house in 3 season sun room with door opened to main house and ceiling fun always on. The stoves are in opposite ends of the house.
Just did some research. It may be not heat source. It may be pepper plants flowering and even having small peppers right nearby. I may try to move tomatoes to a different porch. It is not that warm, but I can add electric heater…
@zendog: No, that actually bothers me even more - I would understand why leaves with edema die - cell collapsing… But low leaves do not look affected as well as their stems.

Thanks for the clarification on where you are seeing signs of edema. I had thought I’d seen some edema injury on the leaf stems when I zoomed in to the picture, but it wasn’t clear enough for me to be sure.

I still think edema may be the culprit even if you don’t see it visibly, since you noted you see some and it can be caused by the narrow bandwidth of a lot of LED lights, which tomatoes are particularly susceptible to and which seems like the biggest change in the environment you are growing in. I learned this by seeing it hit the tomato rootstocks I grow for grafting when I switched from florescent to LED lights a few years back. I lost an entire tray of seedling maxifort rootstocks when the edema was so bad the leaves all wilted and dropped and there were raised whitish welts deforming the stems. It doesn’t seem like you are overwatering, your setup seems airy enough, etc. so edema from excess moisture seems less likely, which is also why I’m thinking it is being triggered by the lighting. I would be even more suspicious if you have peppers in the same environment that aren’t really showing much if any edema, since peppers seem quicker to get edema than tomatoes when humidity/excess water is the cause, but aren’t as impacted by the lack of the reduced spectrum of LED lighting. Also, the leaves aren’t yellowing, showing any obvious external disease, etc.

The modern tomato rootstocks seem the most impacted by this issue, but it definitely can impact regular tomatoes, although some varieties are more likely to be impacted than others. Any chance it seems to be affecting one variety more than others?

Here is one article on the issue:

The only other thing I could imagine would be bacterial wilt if it was possibly present in the compost you used in your mix. There aren’t a lot of things that cause leaves to wilt when the plants have enough water.


I think you are right. Peppers are also covered with edema, but that is every year issue until they go to greenhouse, even with fluorescent lights. In your opinion, will they survive another 3 weeks in the same setting or I need to switch back to fluorescent lights? And another question if you know the answer for this one. I do not have a good place to set a greenhouse for future years, but if I add skylight(s) to the roof of the sun room, will edema issues be less damaging?The lamps are thin and at 8’’ distance, so it should be enough space between for sun light to penetrate. Looks like edema is caused by wrong light specter. Does sun coming though the glass has correct specter, or it loose it, like it loose UV rays?

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Some LED lights do have a broader spectrum (and include UV and IR emitters) and those can solve the problem. I’ve found LED light sellers are very lose with their definitions of “full spectrum”, “daylight” etc. and you really need to see if they provide any spectrum map so you can see if there is really and IR and UV and how much compared to the rest of the light. I also tried adding a separate UV light, but it may not have been quite high enough in the spectrum since I had some issues. Like a lot of this stuff, you test things and without elaborate controls and lots of space it is hard to know how much difference each small thing makes.

When I had the issue, it was the bottom leaves that went first (probably because they had been under lights the longest?) and it moved up the plants. I slowed it down by moving them outside on sunny days. I’ve never had a greenhouse, so don’t have that option. Unfortunately moving them in and out is a pain, plus you never know if you get enough warm days early in the season. I got lucky this year with a warm spring and had them out enough that I didn’t have any issues. I’ve also upgraded my lights, which has helped a bit as well.

I think yours will survive, but it would be great if you can get them outside on any warm days. I don’t really know how much benefit there is from just light through a skylight or windows, since I’m pretty sure at least some of the UV is lost, but it probably helps some. I’ve also kept up higher airflow with a fan which seems to help somewhat but doesn’t solve it since it is mostly a light issue.

Overall it will be trial and error to see what will work for you, but I think yours will survive as long as you get them some outside light. What I’ve found is that if it starts happening I can’t really cure it, but I can try to slow it or stop the progression enough until I can get them outside. I’ve had some issues with my regular tomatoes, but they seem to make it. The hybrid rootstocks though can really be effected, so I have to make sure to get those out in the real sun as much as possible.

Let us know how it goes.

@Fusion_power may have some thoughts as well and may be able to tell if it is something other than edema related to lighting.


I guess this season gave my answer if I really need a greenhouse. I think I do. What also I want to try is to open the sliding door to get some real sunlight in. The problem with taking them outside, I have to leave for work when it is too cold yet. And I can’t trust people who stays in the house whole day to take them out. But just opening the door is easy and doesn’t require much skills. Will see. The soil temperature now is 50F, and starting Sat it should warm up and get more sunny. I may just wait until soil is 55F and plant them out…

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I see three problems. There is a fertilizer balance problem. What have they been fertilized with? I suspect the nitrogen/potassium balance is off. What do I see that tells me this? The slight yellowing at the center whorl of leaves is the key. How high is the humidity? If it is a very humid environment, the bottom leaves may have gray mold. They show strong signs of incorrect light spectrum. Can you harden them off and put them in direct sunlight?

Things to do: Immediately address the light spectrum problem by getting them into some direct sun. No windows, glass cuts off UV. The fertilizer issue can probably be ignored so long as the plants get some direct sun. What temperature are they growing in? If it is below 75 degrees, consider giving them a warmer place to grow for a few days.


The sun exposure is a real problem. It is gloomy and raining outside till next Saturday and it stays like this for several days already. I added Osmocote into the soil mix at recommended rate, but looks like it is something wrong with that batch of Osmocote. They started to show the sign of deficiency a week ago(just three weeks old at that time) . About the same time they started to show edema signs so correcting deficiency was a problem, as I didn’t want extra watering to promote more edema damage… The environment is not humid at all, I would say it is more on a dry side. The grow room connected to the main house and it is fairly dry in… The fun is going all the time, mixing air.
As for the light, I am still searching for the solution. The grow light I have show this picture:
set one (tomatoes):
set two(peppers):
Both lots have bad edema…

These are the bulbs I added to get some UV light onto the plants. I just bought the simple clip on reflector housings from Home Depot to use them with.

I really should do some off-season testing and grow some batches of seedlings just to experiment and see how much, if any, difference this makes since it is very hard to tell if it is better with these. Once plants are suffering from edema, the damage doesn’t go away and some may not show up right away, so it can be very hard to judge the effect without a real control group. I might need to buy a few UVB bulbs to test with as well, since that may be more effective.

Here is the spectrum (supposedly anyway) of the main lights I’m using:

And here are the types of emitters in them:

Notice that although they say the IR emitters are 710nm to 800nm, the spectrum chard shows that they probably don’t really have anything much above 760ish.

Looking at all these spectrum graphs you can see how wildly the light varies among all these LED lights.

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I just ordered two black light flood light, they say they emit 380 nm waves, I want to place them above the lights I have and see if it helps. I also want to do off season testing!