Hmmmmmm...as far as the pruning goes, yes, you'll be spreading the disease from plant to plant unless you dip the shears you're using in bleach between. I foliar feed and had no problems as long as I fed early in the morning so the leaves could dry and there was good air circulation between the plants. I didn't get late blight until it rained for four days here.

If you've had the problem there before, that's why you have it now. If you can't change the location that you're planting in, then you may want to consider spraying a fungicide from the start.

I can't answer any questions about the Daconil...I've never used it. My plants are too far gone and it's July, so there's not a point in spraying them because the season's over.

I agree with srburk about removing the diseased leaves and dipping shears in bleach. Just make sure it is a diluted bleach solution...a 10 to 1 ratio should do fine. Pure bleach may be too much for the plant in my opinion.

It's most likely Early Blight, which is Alternaria solani. It's different from Alternaria canker (different species and symptoms) and it's similar to Septoria in that they're both fungal leaf diseases. If it's spreading rapidly enough to be a real problem, it's probably not Bacterial Speck or Spot, unless you're getting constant rain like some of the folks on the East Coast. :)

Early Blight can cause spots on stems and fruit as well as the leaves. If it's Septoria, the solutions are still pretty much the same, so treat it like EB and it should deal with the problem.

Your plan sounds good in all respects. Mulching prevents soil from splashing onto the leaves, removing the infected leaves takes away the other major source of infection, and Daconil will prevent any spores that still get on the leaves from doing anything nasty. I'm assuming that they aren't watered by overhead sprinkler, if you're worried about the sprays getting the leaves wet.

As for your questions: no, Daconil won't prevent fruit from forming. The pollination is done inside the cone of the flower, so unless you're deliberately squirting lots of it directly inside the beak of the tomato flower, daily, it won't affect things at all.

If you're pruning diseased leaves, do so when the plants are dry, and take care not to brush infected plant parts or tools (or hands) against healthy ones. Carrying disinfectant and a trash bag with you is a good idea, but if you can find something kinder to hands and tools than bleach, it might make a difference with 200 plants. Isopropyl alcohol or Lysol are both possibilities.

As srburk recommends, do your spraying in the morning, so the plants will dry quickly. I notice that you're talking about granular fertilizer and foliar feeding, but missing my chosen form of delivery: water-soluble nutrients. I've had very good luck with seaweed extract and fish emulsion in my nitrogen-poor soil, and if it really needs nitrogen badly, fermented alfalfa tea delivers nitrogen plus a healthy dose of growth hormones. Liquid food can be applied despite the mulch, and (in my experience) needs to be given less often than foliar feeds when the plants are in weak soil.

If you're going to spray both fertilizer and Daconil, do the food first, give it a day or so, then do Daconil. The thing to keep in mind is that Daconil works by coating the leaf with a physical barrier; the antifungal effect only lasts as long as that coating isn't washed away. So you want that "on top", if possible, and undisturbed for as long as you can give it.

Sorry it took so long for me to get to this; it's been a hard week. :) I hope it helps.

--Alison

Thanks to all for the input, I appreciate it! Alison, you're right in that there are no overhead sprinklers - the plants are out in a field, basically. And no constant rain here, though there have been some very hard rains, enough to splash up on the plants anything that may be lurking in the soil.

Also, good point about just plain liquid feeding - for some reason I was under the impression that foliar feeding was a more efficient nutrient transport mechanism? But it's good to hear that this has worked for you, since it sounds like you're dealing with a similar situation in terms of poor soil.

Since right now disease control and fertilizing are equal priorities, and I don't get out to this plot that often, what I'm going to do tomorrow when I go out there is put a bit of lime and gypsum around each plant (BER was a HUGE problem last year, not just in the first tomatoes either), water them at the base with a seaweed/fish emulsion mixture and a pinch of Scotts (17-19-29), carefully cut away diseased leaves/branches (I think I'll make a spray using rubbing alcohol and water to disinfect), put down mulch, Daconil the heck out of them. See what happens. Will report back at some point. :-)

Thanks again for taking the time to offer advice - you guys are great! :D

GG

GG, if you have clay, don't bother with the lime and gypsum. Mulching should deal with the BER, as moisture fluctuations are the biggest factor for you (clay has a medium to high pH, usually, and tends to have quite enough calcium).

If you've done pH tests that tell you it's acid soil go ahead... it's just that in my experience, clay tends to be a little alkaline.

--Alison