Help - Brown Rot intervention?

Hello to all! I am “new” to fruit - more specifically, actually getting anything edible. I have had Apples (6 UofMN) for 16 years - and rarely get edible fruit. Also have raspberries (the Japanese Beetles get most of them), cherries (8 Romance-CJ,R,J), Haskap (10) and blueberries (12).
Last year I experienced Brown Rot on the cherries on all 3 producing bushes. Managed to pick 10 lbs before they were toast - I got 80+ the year before, and had more fruit rot than picked the year before.
So, I spray little - mostly due to incompetence and confusion. Went out to look at the cherries as spring arrives and found the attached pic link:

  • needed the glove to get the phone camera to focus (hoping Google works).
    Is there something I need to be concerned with - and can I do anything about it and get more fruit/less rot this year? Any direction is welcome. I will have to buy everything - I have no chemicals or spray equipment. I have lots of questions and fruit problems - but will start with this (the cherries are my favorite).
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The pictures are not clear. However, I saw one mumified cherry on a branch. One thing you need to do to minmize brown rot spreading is practice good orchard sanitation. Please keep the ground under your cherry trees clean of those diseased fruit. Pick them all up and thrown them out with the trash. Do not compost them.

As for spray, ththere is no organic spray for brown rot. You need to use non- organic fungicide spray. You can use a Bonide product called Bonide Infuse to spray. Please follow the label re. How much and how often to spray.

Brown rot is a common and devastating disease of stone fruit, cherries, peaches, plums, etc.

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Dang - was hoping they would be clear for people looking - really clear on my end. I did pull that (and all) fruit after the pick and cleaned-up. I pulled as many as I could last summer and raked under to clean it up (and put in the garbage). I will look for Infuse and read up on it. Thank you. My biggest concern in the pics is that there seems to be some “dead” spots where there are no buds. Do I need to prune out that branch, from the dead spots forward? It will be some significant pruning - and they are now in the green tip phase.

I always. prune off any dead or diseased branches, no matter what has caused it.

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I was having a problem with Brown Rot Blossom Blight affecting two bush Cherries.They were sprayed this year,using Spectracide Immunox,before the buds opened and it seems to have worked.Only a couple twigs turned brown.The spraying was done with an old Windex bottle,a couple times on dry days.
Reading some about this,it is recommended to use Captan,because the fungus can build a resistance to my stuff.
It hit my Apricots too,so will get them next time.bb

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Pump sprayers are cheap, they don’t last long, but still worth getting. Use acidic water with Infuse for more effectiveness. Captan which was mentioned won’t work at all if not in acidic water. Just add a tbsp of vinegar before you add any chemicals. Or use rainwater. But make sure it is free of particulate matter.

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Sulfur has some efficacy, but you have to reapply after every rain. There was commercial peach production in the humid south before the advent of modern fungicides. They grew cultivars not as prone to rot as many recent introductions.

I’ve often seen peaches produce fruit without fungicide, the problem is that once brown rots enters a site it becomes gradually more difficult to control, but if summers are relatively dry, organic growers around me can harvest beautiful peaches even without sulfur.

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I should have mentioned that sweet cherries are very difficult to grow without splits and rotting cherries when rain comes at ripening time. It is very important to remove rotting fruit immediately to avoid it spreading to other fruit which is quite time consuming with cherries. The alternative is to keep an active fungicide on split fruit right up until harvest. The government says such fungicide is safe to eat!

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Does copper on its own not work for brown rot?

I’m picky about keeping fruit clean. I use Infuse and Bonide’s Fruit Tree and Plant Guard. Both contain effective brown rot fungicides that work using different modes of action. Like you attack the rot on two fronts, not just one method.
This for me has completely eliminated brown rot on any of my fruit including peaches, plums and sweet cherries. Last year I only made 3 sprays. I have used as many as 5 sprays, the last being July 15th. I alternate products using both at least once every year. I like using Plant Guard first as it also has an insecticide I need for PC. I add a different insecticide to Infuse when I spray. PC is a problem here, but if you spray it’s not really a problem.

The brown rot related blossom blight could be killing your branches, these products will help. Captan would help with that too, but not rotting of fruit. You need at least one.
Anyway if you buy Infuse and a pump sprayer it should be about 35 bucks depending on size of each One gallon size sprayer is fine. I would use a pump sprayer and not a bottle sprayer as you have 8 bush cherries, you need a pump sprayer!

For Japanese beetles I tried Milky Spore bacteria and I didn’t really see much of a change. But it can work in certain areas. I also tried a strain of BT bacteria and that seemed to work. After two years I went from hundreds of Japanese beetles to 7 of them. The BT is a chitin eating bacteria. Chitin is the main component in exoskeletons. Someone then told me to maintain a population of chitin eating bacteria is to feed them! So I bought a bag of pulverized lobster and crab shells, which are loaded with chitin and spread it all over the yard. I do not have a problem, at least for the last 2 years. I hardly see any. If they get bad again I will buy more shells. Chitin eating bacteria not only kill grubs but adult beetles too, one advantage over milky spore which only kills grubs. BT or chitin eating bacteria will kill any beetle too, not just Japanese. So for any beetle problem BT bacteria or lobster.crab shells, both probably best!

Only Gardens Alive sells the BT bacteria and they are not cheap! You can get two forms, one for grubs and one for beetles which you spray the bacteria right on the plants. This is an organic product.

I probably will only use the shells as it attracts the same bacteria, feed them and they will come. No need to pay for the bacteria. This may take longer as only the grubs are killed.
For an acute beetle attack or before you can get the shells to work, the beetle spray might help.

This year I got a 50 pound bag of oyster shells for 15 bucks at a local feed store. Just to add some calcium to my potting mixes. I do not like using lime.

Captan is what you need to control your blossom blight and shoot blight. All those cankers are just waiting to infect blooms and fruit.

Applying Captan now will also help against brown rot of fruit. Captan is an important tool in my spray program. Just make sure you add the vinegar mentioned, or the Captan will be worthless by the time you get the spray on.

In fact, with infection that bad I’d probably mix Captan and Infuse. Infuse isn’t that great by itself, but has some benefit with Captan.

Here’s a couple relatively new articles put out by Rutgers. The articles are tailored toward commercial growers, but I think there will be some helpful info to you.

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How do I know a tbsp of vinegar is the right amount to get the correct level of acidity? Not saying the logic is wrong would like to understand it better. Tpsp works if my acidity is 7.5 or 6.5 (naturally)?

You don’t, you should test it, water is different all over. About 5.0 is a good target.
I have commercial test strips, I like them best. I myself use rainwater when I can. It’s about 5.5 here. I said 1 tbsp as that what mine was, but yeah everybody is different.

I guess I can see a need to use Captan. I never had blight. I don’t like it as it damages the leaves on my trees. Thus the amount of sugar it can make. Some say it does not, but I have seen it happen every time I used it. And not happen when i didn’t. It was pretty clear to me what was causing it. I love using it for gray mold on strawberries. Works great!
@Rouse
I agree Infuse (Propiconazole) by itself is less effective. But for me captan is too destructive. Maybe if I had a better delivery system than a pump sprayer I would get better results? So I went to Plant Guard which is Pyraclostrobin and Boscalid used the first spray and 3rd sprays and Infuse or Indar used the 2nd and 4th. Pyraclostrobin and Boscalid are very good against brown rot. Commercial version is Pristine. Again I have zero brown rot, and my leaves are fine. It’s not broke, I’m not fixing it.
I feel Pyraclostrobin and Boscalid are just as good against blight as captan. It works great on gray mold in strawberries too! I should have said to get Plant Guard over Infuse with such bad blight problems. I’m not sure if it can be used with Captan? That would be a double knockout to the blight.And it appears you need the help! You do have a bad blight there. I put my good glasses on to look closer :slight_smile:
I would suggest using both maybe at different times as I do not know if they can be mixed together?

If you are serious about correcting the issue you need to develop a spray program.
Plant Guard would give you apples too, as you need both a fungicide and insecticide. This is why I was reluctant to suggest. As sometimes you only need one, and you have to apply both. This is rarely the case though for me. I would want an insecticide on my cherries too. They can be attacked by many insects. I found if you spray before they find these things (about 5 years for all to find your garden and orchard) you start off ahead of the game.
The haskaps and blueberries should be fine without this product. Can be used for mildews too! Always follow label directions, super important you do for best and safest results.

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As Drew mentions, everyone’s water is different. By volume I believe most 5% vinegars have about 1/24th the acidifying value to acidify waters vs. citric acid.

It’s impossible to develop some algorithm or some exact formula without knowing the buffering capacity if the water you are using.

I’ve tested the pH of our water with a calibrated pH tester. Our water tests at about 9.4 (very high). One tsp per 16 gal. of water will bring the pH down to 5.9. To get the same acidity with vinegar it would take 24 times the amount. Or said another way, one tsp of vinegar should treat about 2/3 a gallon of water to a pH of 5.9.

5.9 pH is low enough for the stuff I spray. Captan has a half life of 8 hrs. at 7.0 pH, so it would be much longer at 5.9. Captan has a half life of 10 minutes at a pH of 8.0, so most water needs to be acidfied when Captan is used.

I think that is a good combination. The only reason I didn’t suggest it to the OP is because the sprays need to be applied before and perhaps at bloom to control the blight, and as you know Plant Guard has an insecticide in it.

I have a correction. It takes 24 times the amount of vinegar by volume as it does citric acid. So one teaspoon of 5% vinegar would only treat 2/3 gallon of my water to a pH of 5.9. I will correct that in my previous post.

I got these comparative values (of vinegar and citric acid) from the USDA canning book. For acidification they state that 1/2 tsp of citric acid equals 2 tbsp of lemon juice, or 4 tbsp of 5% vinegar.

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Yeah very good. I wish they would make them stand alone too. Some like Infuse they do! Plant guard is the only home product with that fungicide, too bad! I’m so glad I have not seen much of blight. One year my tomatoes got early blight and it made the other diseases seem tame. Blight should be a 4 letter word! :slight_smile:

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Mark,
If I mix Captan and spray it right away, does it matter whether or not I acidify water? Just curious.

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Don’t we all spray right away?
The half life of captan is 8 minutes at 8.0 and 32 hours at 5.0

So yeah spray fast so you get 5 minutes :slight_smile:

http://o2yscorp.com/wp-content/uploads/PDFs/PesticideHalfLifeChart.pdf

From what I read Mark’s statement, I did not get the same impression you did, Drew.

Hi Tippy,

Unfortunately, spraying right away won’t help if the water is alkaline, unless the water is acidified.

The half life from alkaline hydrolysis is measured as the time it takes for half the material to degrade. So at a pH of 8, Captan’s half life is 8 minutes. That means even if you could mix the spray up and get the tree sprayed in 8 minutes, you would then only be applying it at half the labeled rate (since half of it already degraded). Then the chemical would continue to degrade on the tree till the spray dried. I’m afraid it wouldn’t offer much protection.

At one time I came across an article which stated most water districts have fairly alkaline water. The federal recommended guideline for tap water is 8.5 pH. Our water district puts out a report every year with how many contaminants are in our tap water, along with the pH.

I suspect just about any water district does the same thing, if you ask them for the report. Our water district used to mail all their customers the report. Now they just put it online.

If you are interested in seeing what the report looks like, here are our quarterly reports for our tap water. I see that last quarter our tap water was 9.6 pH. As I recall, at a pH of 9, Captan has a half life of only 2 minutes.

https://www.waterone.org/about-us/newsroom/water-quality-reports

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