Your Early Blight Prevention Secrets

Everything About Tomatoes
Setec Astronomy
Reactions: 54
Posts: 161
Joined: Fri Feb 21, 2020 11:12 pm
Location: New Jersey, 6b
Contact:

Your Early Blight Prevention Secrets

#1

Post: # 24056Unread post Setec Astronomy
Tue Jun 30, 2020 2:23 pm

So last year all my tomato plants were pretty much consumed by what I think was early blight. It went from the leaves to the stems to in some cases the fruit. Over the winter I researched, and since I am trying to stay OMRI, and I didn't like the copper spray I tried last year, I stocked up on plenty of Actinovate and Serenade, and planned to spray that once a week.

Perhaps I got lulled into a false sense of security because another NJ member mentioned it was a bad year for blight last year because of a lot of rain, and because my plants looked fine, I have only sprayed a couple of times...but last week we had rain, heat, and humidity, and some of my plants got socked with blight really hard, and now (for several of them) it feels like last year where I have basically defoliated the whole plant to get rid of the affected leaves, and am going to be fighting it on those plants for the rest of the season or until I give up on them and cut them down. And I haven't even gotten any fruit off yet.

I did spray some copper yesterday, and that seems to have arrested things, but today and tomorrow we're having showers and I fear it's going to get worse again. I ordered some Daconil which will be here tomorrow.

I'm guessing that I was stupid, and I should have been spraying the biofungals (Actinovate and Serenade) even though everything looked fine (and perhaps doing some soil drench with them)...but to be honest, everything seemed to be going well and I had other things I was busy with.

Or are the biofungals just an expensive way to not get the job done? What are your secrets?

PS I've only been growing a few years, but I don't really remember having any problems prior to last year, maybe I just didn't know what I was looking at, or maybe it's the weather, or maybe something in my local environment...I grow in containers on my deck, the deck is old and the stain is wearing off, is it possible the exposed wood is contributing, either from a moisture or fungal standpoint? I think when I started growing I had recently stained it, so it was all clean and sealed up.
0

User avatar
KathyDC
Reactions: 77
Posts: 80
Joined: Wed Jun 03, 2020 1:33 pm
Location: Suburban Washington, DC (zone 7A)
Contact:

Re: Your Early Blight Prevention Secrets

#2

Post: # 24057Unread post KathyDC
Tue Jun 30, 2020 2:51 pm

Every growing season down here in DC, my plants are affected by blight and fungus issues. Most years I haven't done anything to treat until it was showing, and as you note, by then it's almost too late. Defoliate and hope for the best, which usually doesn't come.

This year, I have been determined to stay ahead of the fungal issues and have so far been using mostly an organic agent that is supposed to help prevent fungus from taking hold, Bonide Revitalize. Its active ingredient is Bacillus amyloliquefaciens strain D747 if you want to research (it's supposed to stimulate the plants' immune response). I did a soil drench of that at transplant, and have been spraying leaves at dusk every week since, sometimes multiple times if it's rainy (which it has been).

But, temps here are now climbing above 90 and will remain that way as the humidity sets in, so I am rotating in some other products. So as of Sunday I added into my rotation Bonide Mancozeb, which is specifically for fighting blights. It is not organic, however. I plan to rotate Revitalize, Mancozeb and Copper sprays weekly, supplementing after heavy rains, through the rest of the season.

For me this is an experiment as I've never sprayed anything as a preventative, but so far my plants look nice and healthy with no signs of fungus, blight or other similar ills, and it's a bit more humid here than what you see in NJ. So I think you would do quite well with some combination of these -- judging from my admittedly limited experience with this new protocol so far this year.

I also have Daconil but am going to keep it in my hip pocket for now, as these seem to be working, knock on wood. I wouldn't think that your deck would be affecting anything. I started in 5 gal buckets and got blight just the same as when I started putting them in the ground so I don't think it's that either, though some fungus issues can be driven by soil-borne junk.
0
Last edited by KathyDC on Tue Jun 30, 2020 3:26 pm, edited 1 time in total.

User avatar
Bower
Reactions: 737
Posts: 1213
Joined: Thu Dec 12, 2019 12:44 pm
Location: Newfoundland, Canada
Contact:

Re: Your Early Blight Prevention Secrets

#3

Post: # 24063Unread post Bower
Tue Jun 30, 2020 3:19 pm

When I started out, I got early blight on the lower leaves every year when the fruit started to ripen. Instead, give them a liquid fertilizer every week when the ripening starts, and the lower leaves stay healthy and don't become a source of blight all over. In the greenhouse, leaves are not rained on so blight tends not to be as bad, you can stay ahead of it with good sanitation pruning. But in the greenhouse there's also a tendency to overcrowd with plants, and that doesn't help.

But outdoors, growing tomatoes that are disease resistant makes a huge difference. Like Kathy said, you can defoliate and they just keep going down, if they're susceptible. Air circulation ie not just keeping them pruned but lots of space around plants may be easier outdoors assuming you have lots of space. If you have to grow susceptible varieties, even a little shelter overhead can help a lot with foliage disease. As with all shelter, the temptation to cram them in must be resisted. ;)
0
AgCan Zone 5a/USDA zone 4
temperate marine climate
yearly precip 61 inches/1550 mm

User avatar
pepperhead212
Reactions: 443
Posts: 482
Joined: Mon Jan 20, 2020 12:07 am
Location: Woodbury, NJ
Contact:

Re: Your Early Blight Prevention Secrets

#4

Post: # 24064Unread post pepperhead212
Tue Jun 30, 2020 3:22 pm

I've had very little rain, which was my downfall last year (no pun intended). Not much you can do, if it just keeps raining constantly -even the disease resistant varieties came down with fungus. I rarely spray copper, unless it seems the rain is going to be letting up - I did that last year, when there was very little rain in the monthly forecast (we switched over to a drought, which I didn't mind!), so I trimmed the plants severely (though all leaves still had septoria spot), and soaked them with copper soap. Amazingly, most of them came back, and I had a good harvest with all that new growth. If the record setting rain had kept falling, nothing would have helped.

I always start out with a spray of Actinovate, spraying new growth every week or so. Then I switch over to potassium bicarbonate once a week, which I spray initially with Surround. When small tomatoes begin to appear, I only spray the bicarbonate by itself - Surround is a pain to get off of small tomatoes - quick to wipe off larger ones.

I just saw one plant - Marion - that looks like it has come down with something this year, out of 28 plants, KOW. I just sprayed it (and the plants on both sides) with some Serenade, and I'll see if it starts to improve; if not, I'll pull it, to hopefully keep it from spreading.
0
Woodbury, NJ zone 6B-7

Setec Astronomy
Reactions: 54
Posts: 161
Joined: Fri Feb 21, 2020 11:12 pm
Location: New Jersey, 6b
Contact:

Re: Your Early Blight Prevention Secrets

#5

Post: # 24209Unread post Setec Astronomy
Thu Jul 02, 2020 10:14 am

I'm kicking myself for not sticking to my original plan of spraying the Serenade and Actinovate every week, but I was trying to get my drip irrigation finished, etc. etc. I learned my lesson over the winter about prevent, prevent, prevent...and then I unlearned it. Hopefully next year I will stick to the plan.

I doused everything pretty good this morning with Daconil, hopefully whatever overspray got on my strawberries (and pollinator basil), which isn't a listed application, won't cause problems, and that I sprayed early enough before it got to be "hot and sunny" which is also a condition under which you aren't supposed to spray. Hopefully another application or two of Daconil will get things under control and I can switch back to the biofungals and/or copper later.

Fortunately the worst-hit plant is a determinate, so I can just cut it down after the fruit comes off...that's if the fruit ever ripens with essentially no leaves on the plant.

User avatar
Bower
Reactions: 737
Posts: 1213
Joined: Thu Dec 12, 2019 12:44 pm
Location: Newfoundland, Canada
Contact:

Re: Your Early Blight Prevention Secrets

#6

Post: # 24213Unread post Bower
Thu Jul 02, 2020 10:36 am

You'd be surprised, SetecA. I've seen fruit grow and ripen on virtually leafless plants! :) It was a PL plant outdoors with super tender and susceptible leaves, but boy didn't stop the thing from setting and bringing up a full set of fruit. I was amazed. Have seen plenty fruit on cherries as well that couldn't keep a clean leaf on em for a week. So I hope yours do the same. ;)
0
AgCan Zone 5a/USDA zone 4
temperate marine climate
yearly precip 61 inches/1550 mm

Post Reply

Return to “Tomato Talk”

Who is online

Users browsing this forum: No registered users and 1 guest