Backyardmomma,

Yellow leaves alone are only a sign of stress, so they can be a symptom of many things. Yellow leaves could, for example, mean the plants are too dry, too wet, underfed, under attack by insects, or have a disease....and there are many kinds of disease including some that are bacterial, some that are viral and some of those are deadly while others are not. It also could mean they are growing in soil that is too cold. If you transplanted them in mid-March, I'd guess that at least initially the soil was too cold and maybe too wet and that might be part of the problem, although it should have corrected itself as both soil and air temps warmed up.

I'm going to ask you a couple of questions to try to help you figure it out and I hope others who grow tomatoes will offer their ideas and suggestions as well.

Are they turning a really bright yellow or a very dull yellow? Do you see any kind of purplish, brownish or blackish spots on the foliage? Do you see any of the concentric rings (sort of like a bull's eye) often associated with Early Blight? It would be peculiar, I would think, to have Early Blight start up in April, but I have seen it start up in May once or twice, so if the temperatures got hot enough in April, I guess it could. Usually, though it is more prone to show up in June.

Also, if you see any sort of circular discoloration on the leaves, is the tissue whole and intact, or are there little brown dead spots in the center, or a lack of leaf tissue in the center like someone took a straight pin and poked a little hole in the center of each spot?

What kind of soil do you have in terms of drainage? Does it drain fairly well? Extremely well? Not well at all? Have you added organic matter to the soil?

Do you, or your neighbors, use any chemicals?

Have you added any compost or used hay/straw mulch whose origin you're unsure of that could have been contaminated by broadleaf weed killers used on cattle pastures?

Are you seeing any lesions of any sort on the tomato plants' stems, especially the main stem? They most likely would be pale tan or light brown in color.

Does your new foliage look normal for this time of year in terms of healthy green color?

Finally, I'm going to link the TAMU Tomato Problem Solver, and if nothing there looks familiar, we might try Earl's Problem Solver. When you click on the link, click on the 'leaf' section and see if anything there looks like your yellowing leaves. That might give us a good starting point because it might help rule out a few things.

The two varieties you mentioned are pretty disease-resistant, which doesn't necessarily mean a lot because resistance is only resistance, not immunity. Tomato plants, though, can be as individual as people...some get sick, others don't. Last year I had Septoria Leaf Spot hit some of my plants, but it was hit and miss...one plant might have a very bad case of it, and the next plant sitting right beside it, even one of the exact same variety, might not show any symptoms at all.

Many diseases live in soil and will stay there almost forever, although solarizing your soil for a couple of months can help reduce their level in your soil. Do you add compost or organic matter every year? I ask because improved soil often helps plants fight disease better. Did you mulch your plants after you planted them to reduce soil splash? With unmulched plants, the rain or irrigation water can splash soil up onto the plant and that soil can carry any soil-borne disease up onto the plant leaves. That's why mulching is incredibly important for tomato plants.
The people I know who have nematode issues in sandy soils usually don't see trouble this early in the year, but I'm not saying it couldn't happen. If you happen to have nematodes, you'll see root galls (swelling and knots) on plants when you pull them up out of the ground. Have you seen any of that in the past?

I'm sure we'll be able to figure this out, but it might take several of our brains working together (in fact, I am sure it will) and also some back-and-forth conversation. So, be patient and give us all time to work through the possibilities and to think about your answers to our questions. Now, when you have time, look at the link and see if it helps you rule anything in or out.

Dawn

Here is a link that might be useful: TAMU Tomato Problem Solver

I forgot to add that it is very common for the lowest, oldest leaves at the bottom of a tomato plant to yellow and drop. That just means they are old. Normally, when that happens you'll see new leaves coming out in the same spot to replace them, and sometimes the new leaves start emerging even before the old leaves have fallen off. This type of old-leaf yellowing usually does not progress up the plant very much or very quickly though.

Been doing some more investigating thanks to your tips. Thank you to anyone who can help! I think I am going to lose the plants. This might have been what happened last year so I am desperate to figure this out!
Here are some answers to what you have asked-
-leaves are starting to turn a greenish (lime) yellow and then go to a true yellow color as whatever this is attacks the leaves. It has started on lower limbs then moved upward. I would say the color is more bright than dull
- No splotchy or moldy areas like those seen on pics online. The leaves start out yellow and no spots. As this has progressed the affected leaves develop a few speckles of brown, then they begin to exibit the "pin hole" that you have described. This "pin hole" is a very late symptom and I only see them on the leaves that are pretty much already gone. On a few of the pin holes the tissue is no longer intact and the hole is open.
- no leisions on the stems.
- new growth is green but has a wilty appearance. The plant just looks very sick.
- The soil drains pretty well. I have added multiple applications of organic amendments. I have added bags of top soil, composted manure, bone meal, leaf mulchings, and some sand.
- This year I tried cotton burr compost and tilled it in the same day I planted. It was from lowes. I also threw some in the plant holes before planting. The only thing suspicious about it was that it had a moldy smell (not chemical) more than regular manure I have purchased. The bags were wet so I attributed it to the moisture. Appearance was fine. Do you think this could have been contaminated with a defoliator or something?
- I did not mulch around the tomato plants after planting. I usually do but was waiting on some seedlings to come up that I had planted before mulching. BIG MISTAKE because I prob. just spread whatever was in my soil.
- I never use chemicals but am unsure if my neighbors have this year on their yard. There are privacy fences between us but I guess the wind could still blow stuff in our direction.
- I have added sand to the soil two years ago. I have never seen knots on my roots, and I do look at them when I pull them up.
- Nothing really looks identical to anything online but I am wondering if the pinholes will give you a clue.

Please share any insight! I really want to figure this out and learn from it! I do think I am going to lose these plants. If I replant how far away do I need to be?

I would ask did it rain hard enough to splash on the lower leaves or do you water from the top or at the base also it could be a potassium issue.I am just giving my thoughts from up in the Big Sky Country.............