That could be severe aphid damage, but you don't mention seeing any pests. Have you checked the undersides of the leaves for sap-sucking pests? Hard to tell with the low-res photos Houzz allows, but I think I see bumps that could be pests.

If not pests, then likely oedema from waterlogged roots.

There are no pests at all. Generally we deal with the tomato hornworm, but I haven't seen anything yet.

The spots are new, but do not appear to be any sort of pest. I am stingy with my watering because I know tomatoes love heat so I don't think its waterlogging. I'll experiment with a few things just to further rule them out.

Thanks for your comment!

I am curious, what is the reason for growing your tomatoes in boxes instead of in the ground?

Where are you located? Have your tomatoes been suddenly exposed to hot, dry wind?

April: I am stingy with my watering because I know tomatoes love heat so I don't think its waterlogging.

Tomatoes don't love heat the way eggplants and peppers do. They prefer moderately hot daytime temps in the 70s and 80s. Above 90 degrees and they'll often stop setting fruit, drop blossoms, etc. In desert areas, southern areas with strong sun, etc., tomatoes can actually benefit from filtered shade during the hottest part of the day, and in the southern states, people usually plant a spring crop and a separate fall crop, as tomatoes don't survive the hottest part of the summer well.

Is it possible you have been too stingy with your watering? Most people who make a watering mistake overwater, but growing in a container or very raised bed can make it easy to underwater.

It's also possible that, if your weather has been extreme, the tomatoes are just showing stress.

@windberry: I'm growing in boxes because we moved and I don't have the same space for my garden that I've had before. Hoping to tear up the ground next year.

@gorbelly: my experience (past 5-7 years) has been that my plants have flourished in the heat. In past summers I only water a few times a week and they are happy! I have been doing alot of reading about using planter boxes and watering more frequently seems to be what is necessary. However, one of my plants started showing signs of overwatering, so I stopped watering as much. I also try to check the soil for saturation levels before I water. I'm in Northern California where summers get up to 110 at times, but averages mid 90's. The weather has been erratic this year. It's mid June and and it is 68 at 1pm today. It'll be 100+ this weekend. Maybe they are stressed, I don't know, I've just never experienced this type of thing before so I really appreciate all the feedback!!

April: I believe that your problems are related to the growing medium. Something toxic used to treat the wood or something toxic in the soil. Limited size and depth of the boxes is also detrimental to the growth and health of the plants. Plants that are already struggling are also more vulnerable to the extremes in the weather.

My advice: start preparing for growing in natural soil the next year.

Container plants show signs of stress in their foliage more than in-ground plants. That makes sense because growing in-ground provides a big buffer in terms of moisture levels changing more slowly, soil temperatures staying more steady, etc... it's just a function of much greater mass. Containers fluctuate root temps and moisture levels much more quickly. Thus, container plants are more susceptible to physiological leaf roll, etc.

It doesn't mean that there's anything toxic in your containers. It also doesn't mean you can't grow plenty of tasty tomatoes successfully. Your foliage may look more stressed, but, if you feed and water the plant at appropriate levels and the containers are large enough--and yours look large enough provided they're at least a foot high--it doesn't necessarily have to have much of an effect on the plant's production or vigor.

Many people grow huge numbers of tomato plants successfully in containers. In parts of the country where soil disease is common, sometimes it's the only way to grow heirlooms that are not resistant to nematodes or soil disease. Other people don't have enough sun in available in-ground spots.

People like Craig LeHoullier grow their tomatoes very successfully in bags and bales of hay on their driveways.

Don't let the perfect be the enemy of the good. If you don't have appropriate in-ground space, don't give up just because some people think that ONLY in-ground tomato plants are worth growing. Because that's definitely not true.

gorbelly: I agree that not everybody may have a piece of land for growing Tomatoes. For them growing in containers is an option. But for those who do, growing naturally in the ground is the best option. April says she does, it just requires some work to prepare the area for planting.

April: My advice for you, April, is to dig the soil as deep as you can, add organic amendments if you have them, and sow the cover crop of Alfalfa. It is far from being too late. Plant your Tomatoes next year in there, deep, adding some compost to the planting holes, preferably a month or so before planting, if not fully decomposed. And don't use this year's diseased plants in your compost.

Growing in-ground is definitely easier provided there's no established soil problems. It's not always "the best option". It depends on a lot of factors. Nobody should feel that growing in containers is always inferior. Sometimes it's inferior--it really depends on what you're willing to do and the methods that work for you.

Since April is an experienced gardener, I assume she knows how she can prepare her ground for planting next year if she has good spots for growing in-ground. I don't know how helpful it is to her TODAY with the issues she's having with her plants now to tell her that growing in-ground is better.

Thanks to both of you. Yes, I'm very experienced with an in ground garden. Many MANY people grown gardens successfully in containers. It's definitely not my first choice, but here we are. IF in ground was an option this year we wouldn't be having this discussion right now. However, unforeseen circumstances did not allow for that to be the case this year.

This discussion is healthy and I'm learning from you. Besides getting to know y'all is an added bonus!