Hmm....Just to clear this up, do you have early blight or septoria leaf spot? They are two different diseases. Each can be treated fairly similarly however. It would also be helpful if you posted a picture so that we can have a look at the disease progression.

These are two diseases we commonly deal with here, especially in wetter seasons. In my personal experience, cutting foliage is useless once the disease is fairly active on the plants. If I see a bit on the lower leaves, as I commonly do, I will just prune those, and it does help being that it's not well established in taking over the plant; but if it's actively progressing it's useless.

An absolutely crucial control method I have found for both leaf spot and blight is placing the plants in a spot that gets morning sun as early as possible. Why? So that morning dew, if any, doesn't sit on the plants for hours and hours until the sun finally hits. This is a fantastic breeding ground for fungi. Of course, those conditions are not always optimal. That's why I also use a fungicide, normally Daconil. If going organic, there are many others (serenade, copper, etc.), but I prefer Daconil to its organic counterparts. I spray about every 7-10 days, as per instructions, and it certainly works. I may get a bit of disease develop on the lower leaves as I mentioned before, but it's well controlled and will not progress very easily. Both morning sun and fungicides combined is a sure way of controlling the disease under normal conditions.

Of course, preventative measures don't apply to the diseases you already have. You can try a fungicide, like Daconil for example, but fungicides are better used as a preventative measure. At this point, assuming it's blight or leaf spot, I would just use a strong fungicide and hope for the best. They may come out of it and push out new growth.

I also notice you are using a high nitrogen fertilizer? Based on my research, tomatoes fed high nitrogen fertilizer will tend not to produce fruit due to focusing on foliage production with the abundance of nitrogen. This could be different in a situation as yours with losing quite a bit of foliage as it is, but still a possible concern. Hopefully someone else with a bit more experience than I have will chime in on that.

Good luck, and keep fighting the battle. Septoria leaf spot sucks :(

Here's an article that may be helpful:

https://njaes.rutgers.edu/fs547/

Hi there! So yes, sorry, I was incorrectly conflating the two. They have septoria.

So just to clarify, the plants have a lot of fruit already and some ripening; I just did the high-N yesterday to try to encourage some vegetative growth to replace the severe hack job I did to get the affected leaves off. :(

That morning sun idea is a good one. I have been wanting to develop an
area on the SE side of the house so that will be the plan for next year. They are west now because of current deer protection measures. Though ironically, the plants I put over in the deer superhighway to test out a deer spray are thriving and disease-free and unaffected by the animals. Go figure!

Isn't it a shame that in June you figure out what you should have done in April and have to wait a year to do it? :) And, truly, I should know better. I used to work with grapevines in Napa; would have reached for the copper a long time ago there. How much of gardening is kicking oneself???

I will try Daconil too and keep treating as long as we still have these gloomy cool mornings. Hoping we can limp into some more ripening before I have to call it.

Thanks for your thoughts. I really appreciate it.

RE waiting until next year- quite the contrary! Depending on how long your growing season is, you may be able to squeeze out a fall crop of tomatoes, eliminating the mistakes made in the first crop. Our average first frost is normally sometime in mid October, so this is really the latest I'd be wanting to start any. They will grow very quickly in the mid summer heat. I started indeterminates for fall at the beginning of the month. Indeterminates may not give a huge crop before frost considering that it's quite staggered, but if you're interested in preserving tomatoes you may try determinates, which crop all at once under normal conditions. I'm trying my fall tomatoes in containers for various reasons: In the cooling days of autumn, the containers can heat up more easily, though they can also be more susceptible to cooler nights- a toss up! Also I have no space in my garden at this time of year to put in fall tomatoes with all other fall crops being started.

Don't beat yourself up too much. Making mistakes is the best way to learn! Some call it "experience", a very valuable gardening tool. Years later, you won't be telling people a method doesn't or does work based on what you read on the internet years ago; instead, you'll be telling them based on experience!

Well, thanks. It's just my second summer back on the east coast after 11 years in the very odd growing climate of San Francisco and I'm still re-learning everything I forgot over that decade. Live and learn, indeed!

Determinates are a great idea. I have some Oregon Spring planted as an experiment--they were my only tomato success in SF and have great flavor--so I have those seeds around and can start on a heat mat to accelerate. Who knew I would need Oregon Spring tomatoes in a DC summer? Will see what else I can find on the sale racks around town--with the shortest growing time! :)

That really would be tough. Two completely different climates!! I would imagine tomatoes wouldn't have the fungus issues in SF so bad due to dry air? Am I correct on that?

I started some Old German and Pruden's Purple. Probably not the best choices for early fruit setting before frost, but they looked interesting! Keep us updated on how they progress.

My in laws live in central CA and their tomatoes are always disease free with no special effort. The first time I saw them I said “wow, yours are green all the way to the ground!”. Im in Virginia too, and I don’t think I’ve ever seen a disease free tomato plant in August. In the whole state. I just start a new batch in June and rip out the old ones in August.

Yes SF had no tomato fungus issues despite the fog but the main issue was getting enough heat for fruit set. And ripening. One year all I could do was collect greenies for salsa verde. :) Can you imagine insufficient heat?!

Scrounged up a few late-season options today. The sale racks are pretty great in late June!

And have now done what I can do with chemicals and waiting. :)

It's a bit of the opposite here....I'm having a hard time finding seeds in stores! Most small, local feed stores have good selection still though, and they're often cheaper anyways.

Insufficient heat is hard to imagine honestly, especially with today's high of 94!!