Bleach as a Brown Rot Fungicide?

@Kenny_Zone7B_NYC may still have some in small containers for sale. You can reach out to him if you want to try.

If you notice varieties you have that are very prone to rot, you could take them out and keep only the less susceptible ones.

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I wondering, how do you know how much to use in the sprayer? Are you converting oz per acre to amount per sprayer?

There is some member who is good at math and calculate it for me. @BobVance is one of them. I use Indar. Scott has it at 1/4 tsp per gallon of water.

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I am OK with math, I just don’t know what amount of water is needed per acre of fruit trees

I sucks at math so I am married to a math teacher :grin:

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For a short term solution I would mix Captan with Myclobutanil and spray both together. Captan is pretty effective against brown rot but it’s easily washed off if you get a lot of rain. Myclobutanil is absorbed into the leaf tissue and much more rain fast. It’s much less effective against brown rot but if you get a lot of rain and high winds it will provide some protection until you can get out and spray again. You might also shorten your spray interval to 10 days or less.

Bleach would kill fungus but as soon as it dries it provides no protection. Plus it may damage leaf tissue and its not legal to use as a fungicide any way.

Long term your best bet is Captan mixed with Indar. Using the Captan at either the full or half rate. You could also substitute Propiocanazole for Indar but I don’t think Propiocanazole is labelled for apples so you would need a separate spray mix for apples.

For you guys that have lots of trees Olpea calculated costs on a per acre basis.

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I think I’m pretty decent at math (98th percentile on sat, engineering degree, etc), but according to my wife, I’m bad at math. Evidently, the math classes in China are much more rigorous. And it probably doesn’t hurt that her father was a math professor (now retired).

She introduced me and our youngest daughter to 24 the other day, a game where you lay out four cards and the first person to figure out how to get them to equal 24 (using any combination of basic operations and parenthesis) wins. I was only able to win 2 of ~10 rounds and our daughter didn’t get any. And my wins were the type where you just add them all up (I was quick enough at that :slight_smile: )

Gardening does give you a chance to actually use math. Not just in calculating concentrations- I’ve even used trigonometry to calculate ground elevation, shade angles from trees, etc. How many people can say they’ve used trig outside the classroom…

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Bob,
I am waiting to know how math could be applied to eliminate pests like squirrels, groundhog, raccoons, opossums and the like?

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Range , windage, elevation ,and for those long shots , earths rotation must be factored in, so math .and a bit of luck … Too

Math doesn’t eliminate them, but it shows you what will happen if you don’t (figure how many offspring per generation when ample food is available (your trees…), how long the generations are, etc). Don’t forget rabbits- they breed like…rabbits. So, if you eliminate earlier generations, then they won’t be around to have kids and grandkids.

I saw a youtube video recently which relates in a grim way. During WW 2, Russia lost so many people that every 20-25 years, their birthrate drops when the kids, grandkids, great-grandkids, etc of those people would have been having kids of their own. Only 20% of the Russian boys born in 1923 lived to see their 23rd birthday in 1946. The end result is that while Russia was 3rd in world pop in 1900, they have barely grown at all while most of the others on the list have grown 3X or more (US from 76M to >300M).

Now, while it is a bad for people, it is generally a good thing to have all the squirrels, raccoons, etc die. The trick is finding a way to do it.

And while Russia doesn’t have enough immigration to boost their population after 80 years, it is a lot quicker for new squirrels to move into the area. :frowning:

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Glad you started this post. A few days ago I didn’t have a problem with brown rot and was happy my previous sprays where successful. I checked this morning and I have it now. 4.6 inches of rain in the last two weeks. Only a few sunny days in two weeks. Woke up to 95% humidity the last few days. I was waiting for a few dry days before spraying but that was a mistake. I removed as much of it that I could find and sprayed with Captan and Propiconazole, the only safe fungicides I had available.

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Kevin,

As mentioned, myclo isn’t the best for BR. Sooo, alternate spraying every two weeks with myclo and Captan is closer to spraying once/month for brown rot.

In very frequent/high rainfall the fungicide protectant is washed off fairly quickly. In lots of heavy rainfalls, it may require weekly applications under those conditions for commercial applications. The problem is that while you are not commercial, you are quickly accumulating enough trees that they start to act like a commercial orchard. In that case, you want to keep a protectant on. That may mean reapplying weekly after heavy rains.

Regarding bleach. As mentioned, I wouldn’t try it. Chlorine is very reactive to organic matter. Although I haven’t tried it, it’s likely, imo, that using enough bleach to effectively treat brown rot, will have a substantially negative effect on the foliage, and possibly the skin of the fruit.

If it were just a matter of spraying our trees with bleach as a rescue spray to control brown rot, I would have done it long ago. If not for anything else, but for the cost (One can obtain high powered chlorine pool tablets, very cheaply, which are the equivalent of countless gallons of bleach.) I’m not at all optimistic bleach would have a therapeutic effect on BR, unless the dose was so strong to also have a phytotoxic effect on the foliage.

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I use a 10% bleach solution to treat stratified ginseng seed b4 planting. 5 minutes in 10% solution bath. Often when ginseng seed is properly stratified the seeds will be tailing… the little root starts will be poking out the seed a little and the seed will be starting to crack open slightly.

It sure does not hurt viable ginseng seed… I always had great germination rates.

Never tried that on peaches though. My early elberta peaches started ripening mid june… and even with no spray… I got several nice peaches off that tree.

Towards the end … I saw brown rot kick In and took a lot of them out. First time i have seen that here. My Reliance ? tree started ripening fruit 2nd week in july… and I lost 90% or more to brown rot.

I love peaches… but it seems to be impossible to get good ones now days unless you spray them with things I am just not willing to spray on my food.

TNHunter

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Yes, for sure, and something even better is Bonide’s Fruit Tree and Plant Guard. It contains two fungicides that have a different mode of action compared to Indar and Infuse which have the same mode of action. In other words they attack the fungi differently. Using both is like having two fronts in a battle and you can out flank brown rot. I get ZERO brown rot doing this. Now the bad news, Plant Guard looks to have been discontinued. I bought as much as I could before hand.

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If you want to grow peaches without synthetic fungicides to control brown rot you are unlikely to be successful in the long run unless you live in an arid region. All of the peaches you buy in a grocery store are sprayed with synthetic fungicides and insecticides.

There are some things you can do. First plant only peaches that have some resistance to brown rot. Glohaven, Babygold #5, Harcrest and Elberta have some resistance. You also may have some success with peaches that ripen during a period when rainfall is low even if they are not resistant to brown rot. Remove susceptible varieties especially highly susceptible ones. These trees act as brown rot disease reservoirs and can make conditions in your orchard much worse. Spraying sulfur on a regular schedule will help and it’s certified for organic orchards. A full sun location, good air circulation, and pruning the tree to be open will also help.

A friend of mine also wanted to grow peaches organically. I told him it would be very tough but I would help him pick a good tree. Ultimately we decided Glohaven was the best choice based on its resistance to brown rot and bacterial spot. It also can produce very large peaches but that was a minor consideration.

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Very true. I feel though if you want to stay organic grow easier fruit and lot’s of cool things like Jujubes, mulberries, filberts, and many others too. I added Shipova this year for example. I think it takes about 8 years to fruit though.
Worse than peaches is nectarines. That fuzz stops a lot of things!

Yes. 1000 times yes!

Wait…did you really just suggest that I might need to start spraying once a week? I just got a cold chill down my back at the mere mention of trying to spray anymore than I already do! haha. But I understand. And based on you and other responders here I had decided exactly what you said- my alternating of myclo and captan effectively meant I was treating for brown rot once a month, which clearly wasn’t enough. Even though I understand the science (somewhat) and trust you implicitly, its just hard to wrap my brain around the fact that myclo can be so great at treating some things like black rot on grapes (it is downright miraculous how well it ended that problem for me) and yet not be much use at all on brown rot. I’m sure you have told us 1000 times, so I’m sorry to ask, but can you remind me what you use for brown rot?

And, btw, I promise I’m not just saying this to be nice or inflate your ego, but when I was wondering if I might be able to use bleach as a last-minute rescue for fruits that already had brownrot fungi but weren’t yet showing it, I literally thought “if it was that simple I’m sure Mark would have been doing it by now” ! Really.

Whatever you are using for BR, what is the PHI on it? Is there anything that can be done once you start noticing that as peaches on a tree ripen they immediately get covered in Brown rot? Meaning BR fungi (spores?) are probable already all over that tree and its fruit but still hasn’t ruined unripen fruit. Or by then is it basically just too late to do anything?

I’ve read that Peracetic Acid can kill brown rot but maybe not stop it from reappearing. I need to do more research on it. @JoeReal made some mention of it when he was talking about his “Salad Dressing” spray. If it works it would be an organic spray that could be used a few days before harvest (it it’s not raining). Walmart had a clearance on a Peracetic Acid and peroxide produce for 1$ and bottle. I went back to the store yesterday to buy all of it but sadly it was gone.

Generally, for Captan the recommendation is if you receive 2 inches of rain you should reapply as soon as you can. In periods of frequent rainfall you probably should plan on spraying every 7-10 days. If your mixing it with Indar you could probably stay on the 14 day schedule since Indar is absorbed into the leaf tissue just like Myclobutanil. It’s also possible if you just went back to your original schedule where you sprayed Captan mixed with Myclobutanil you would be successful controlling brown rot. Myclobutanil is less effective than Indar but your last year’s experience shows it is probably effective enough.

Under Eastern conditions, most Universities, crop specialists and people on the forum find Captan and Indar to be much more effective fungicides for combating brown rot on peaches than Myclobutanil . The University of California reverses the effectiveness ratings as seen in this chart.

UC IPM: Fungicide Efficacy and Treatment Timing for Peach

Why I don’t know. Maybe they have a different strain of brown rot. Also they have a different climate may be that’s it.

It also appears that small green peaches can be infected with brown rot and show no symptoms. Later when the fruit ripen these dormant infections become active and suddenly you see brown rot everywhere. See this link

Also Captan, Sulfur and Daconil are protectant fungicides. They protect healthy leaf and fruit tissue by killing spores before the spores infect the leaves and fruit. They aren’t really effective once the fungus has infected the plant tissue. Some fungicides have a curative effect. Indar and Myclobutanil both do but still the curative effect is limited.

As far as why a fungicide is effective on one fungus and not another it comes down to the genetic differences between species. For example I take Tylenol and I am fine but Tylenol is lethal to cats. Both me and the cats are mammals so why is it toxic to cats and not to me? Basically, our genetics are different.

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