Using captan

Any particular products that has this to look for in the stores? I tried Google but all I could see was the oils themselves to buy. I agree with you, the sticker it is on the leaves the longer it will stay. BIG problem for me last year. It much rain over and over again for water based products. I could not get the sprays on as fast as the rains washed them off. Horrible year for trying to keep the fruit edible .

Another good thing to get there is a Ph tester to make sure you don’t overdo

I use ColorpHast strips in the lab at work for things when using a pH probe for accuracy isn’t required. They are more pricey than your typical litmus paper.

Those look good, I like the limited range strips though. I think this is the product I used. Someone pointed me towards it. This is the range I need to test more closely.
Easy to get it right with these strips.,MDA_CHEM-109542#anchor_PI

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These were the leaves last season. I have no idea if it’s bacterial or fungal shot hole. I did noticed the copper soap I have is labeled for bacterial spot so hopefully that helps with this. Whatever it was only hit my nectarines and not any of my plums or pluots.

McolorpHast pH 4.0-7.0 from and elsewhere I’m sure.

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Thanks much for the link, OK same brand.
Looks like they only sell the full range strips, the price is better. I still like the 4-7 as you can get really decent accurate readings. But for general use the full range will be fine too.
Links are book marked again, time to save bookmarks!

Actually, so little is required of citric acid to treat water that this source would be adequate for anyone that is not a huge commercial grower, I think. I can’t remember off the top of my head, but I don’t think I use more than 2 TBS to treat 25 gallons of water. I usually use a penetrant that also acidifies more than adequately, so my quart of citric acid will last me a lifetime.

Be careful about using it in the kitchen- I ruined a batch of hot-sauce by using too much.

I have it on hand, but use it for canning. These pH strips we have been talking about could be useful to me in the kitchen too. Products with a pH of less than 4.6 can be safely canned without needing a pressure canner. If a product is close, citric acid can turn the corner, and does not change taste unlike lemon, lime or vinegar. Fruits like figs are basic and if you make jam, best test pH if you plan to store on shelf and not keep cold. The Botulism organism cannot survive in these low pH environments. If higher you need a pressure canner to get high enough temps to kill spores. With acidic products, it can’t grow so no need to kill spores.
I can make jam with only boiling product about 6 minutes, average is around 8 minutes. Less vitamins and other long complex nutritional molecules are destroyed by the boiling process. 12 minutes is a safe amount of time and will kill all fungal spores. It should last longer on the shelf, yet be more nutritious than anything you can buy.

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I have some captan, not sure which formulation. I was trying to avoid copper because I can’t practically keep my dogs away from the grass under my trees. The main problem I have encountered thusfar is scab on my peaches. I was debating this year trying to do a limited spray of Triazicide and Immunox. (It’s easier to keep them in a couple times a season rather than almost weekly by some spray schedules with our humidity and rainy springs.) Anyone have thoughts about whether I should do Captan + surround baggies, vs Captan + Immunox + Triazicide? This is supposed to be “the year” for my apple espaliar, and my peaches and plums should be reaching mature production this year (albeit trimmed for size heavily a la BYOC).

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Like Alan, I’ve also ruined a batch of Salsa using too much citric acid. There was a time I was trying to see how low I could get the pH without noticing any difference in flavor. Too much citric acid and the salsa becomes too sour. 1/2 teaspoon per quart is about right (I use about the same amount of sugar to balance out the citric acid).

I bought 30 lbs. of food grade citric acid years ago and am finally starting to run out, but I use quite a bit more the last few years. On a 400 gal. tank I use about 3/4 of a cup at a time. I agree w/ Alan, a quart should last a long time for most people.

At one time I was concerned citric acid may lose potency with age, (like some pesticides do). My daughter told me it should be stable, but asked her organic chem professor about it a few years ago, just to make sure. Her prof. said citric acid should retain potency for a very long time (years and years) as long as it’s kept under reasonable storage conditions.

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I use lime in my salsa, it goes with the taste better, but I don’t can salsa anymore, I much prefer freshly made, so I make it fresh weekly when my tomatoes are ripening.
If I ruined a batch i would add baking soda to neutralize the citric acid.
My favorite salsa is roasted tomatillo salsa, I grow them once in awhile.

Mr. Guy,

I’m not sure how to advise on your specific questions. As a general observation, I will say I’ve had good luck with captan. It provides excellent scab control for me.

It is critical the water be acidified when using captan. It breaks down extremely quickly in alkaline water (most tap water is alkaline, or even highly alkaline - ours is around 9.3 pH). It should also be used at the full rate if used by itself and spraying has been inconsistent.

I use it at the half rate if I’ve been able to be consistent in my sprays and still get very good control. Sometimes I will mix it at the half rate with something like Topsin M, Propiconazole, or Indar and get excellent control of brown rot.

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I guess I just struggle with figuring out which fungicides are most effective for what situations, especially since I am trying to be prophylactic and not responsive. I really have three questions, if I have Captan, when would I need copper (which I want to avoid) or Immunox. If I get surround infused baggies, do I need Triazicide? Thirdly, am I making this hard on myself with my extremely limited amount of potential fruit, and would it be easier to just follow a synthetic low spray schedule and spray sparingly if I am not particularly riled up about either blemishes or chemicals.

I didn’t know I needed to acidify the water last year, so hopefully that will make a difference this year.

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I suggest you look up @alan 's low spray regimen here. It combines the"'prohylactic" component ,which I think is more important for the fungal threat as fungal threats are more weather related, along with the comfort that it is also is hitting the insectoid threat based on a more time focused way.

For me the bagging is just too time consuming so I limit it to those fruits that may need special attention on a year to year basis like if some tree had a particular problem that effected the yield and I want to insure some harvest survives.


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Olpea, In your climate when do you start Captan preventively for
Bacterial Spot on peaches? Last year I was not aware of the problem
until after the symtoms appeared. I’m in 6b Coastal Connecticut.
I use Captan on my apples for Fly Speck and Splotch starting around
4th of July.

What varieties suffered it? I don’t see a lot of Bac S. in your area- but I only have a couple of clients actually on the water.


If you have bac. spot (you can generally distinguish from scab on peaches because bac. spot affects the leaves and fruit, whereas scab generally just affects the fruit) bac. spot won’t be responsive to Captan.

Copper or an antibiotic are generally used to control bac. spot on peaches. Even then, it can be very hard to control on susc. varieties. I can control it with an antibiotic (mycoshield) in my backyard, but can’t control it at the orchard. Just too windy and dusty there to control it, so I’m really starting to focus on removing susc. varieties.

Sorry, got confused between my diseases and treatment. Alan- All of
my peaches had what I believed to be BS Winblo, O Henry and
Indian Free I treated the peaches with Mycoshield eary two weeks
from Mid July onward. Sorry, guys my question should have been
When would you begin to spray preventively for BS using Mycoshield?

Early is better. The label says start at petal fall, which is when I start. I’ve read bac. spot is better controlled with the early sprays vs. later sprays (unlike brown rot).

The old label limited you to 9 antibiotic sprays (I think) at least with the generic Fireline. The new label of Mycoshield looks like it’s a 12 lb. per acre seasonal max, which would be like 12 sprays at 1 lb. per acre application.

It doesn’t even take 9 sprays to control it, if you spray early and don’t have too much pressure in your backyard orchard. I think in my backyard orchard, 5 or 6 sprays controls bac. spot completely. However, it’s pretty much impossible to control under very high pressure. I spent $500+ last year on Mycoshield at the orchard and still wasn’t able to control it on susc. varieties there.

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