I’ve been gone a lot and haven’t been in my orchard as much as I need to be. I see several peach trees that look like they have peach scab on the peaches. .
Is there any benefit to spraying a fungicide now or is it too late for this crop?
Yes it is.
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I think peach scab can infect branches too. Maybe spray after you pick the fruit. I sprayed once with Immunox at the beginning of June here and it seems to have stopped the disease this year. My peach were affected last year with me just using sulfur sprays.
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Thanks so much. I did some reading from several university sources so I should know what to do next year. This is the first year I have seen scab on my peaches.
@PharmerDrewee. I had read sulfur is an option. Thanks for relating your experience. It’s good to know you had more success with Immunox this year.
If I were you, I would try to avoid using chlorothalonil (Daconil) due to its limited use. It can’t be use after fruit are formed.
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Thank you, mamuang. I’ll keep that in mind.
I have liked Daconil’s effectiveness on cherry leaf spot. It’s use is more limited, if I am remembering correctly, but it did a better job of knocking our leaf spot on my cherries than Immunox/Captan did for me.
I have to be more proactive next year, now that I know peach scab is here. I also have some brown rot for the first time. It was a very wet, raining spring and early summer, which no doubt contributed to these fungal diseases.
Brown rot, if you don’t have Indar, you can use Bonide Infuse, propiconazole.
For cherry leaf spot, it is fortunately that Immunox is sufficient for me.
As we have more years into growing fruit, diseases seem to increase and pests seem to find us.
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This a follow-up question about brown rot and scab from last year.
I might be a little confused about which chemicals to spray, depending on which do a better job on the target disease.
I bought Bonide Infuse (propiconazole) as you suggested above. I plan to put down a spray either today or very soon. Most my peach fruit buds got frozen this winter, but the ones that are still alive are starting to show pink, so I think it is time to spray for brown rot.
My Zard apricot is in pink too, so I will spray that as well. The other apricots are already blooming, so won’t get spray. I never get apricot fruit anyway, due to late freezes, so I have no idea if they would get hit with brown rot too, but it seems likely since it showed up in my peaches last year.
The Infuse label says spray every 21 days.
I also had peach scab last year so I need to spray either myclobutanil or captan starting at petal fall, continuing every 10-14days. I read a post yesterday where @alan said that captan also takes care of brown rot.
So after the 1st Infuse spray today, should I spray again in 21 days or assume that the captan I spray for scab will also take care of the brown rot?
Would there be harm in applying propiconazole now, then following up with captan after petal fall? Or should I choose myclobutanil for the first spray after petal fall?
And is it recommeded to alternate myclobutanil or captan through the spring/summer sprays?
If you have time to answer and share your knowledge, I would appreciate the help!
No, usually you don’t need to protect against brown rot until after petal fall unless a site has a history of blossom blossom blight, which may not be a common occurrence where you are- it isn’t where I am.
You can spray it about 10 days after petal fall and again in mid-summer and I suspect that will be enough to harvest sound peaches, but I can only speak for my region.
Myclo is said to work well for first stage brown rot- that is blossom blight. The label on the stuff I use says not to use it after the first spray immediately after petal fall, or closely following. Use the Infuse the 2nd spray.
So the label does say you can spray peaches with it?
The Infuse label lists apricots, cherries, nectarines, peaches, plums and prunes.
For brown rot, our KState Extension guide, MF3430, recommends spraying at pink, just before buds open. As well as at petal fall, shuck split, and every 14 days. Stop applications 14 days before harvest.
KState Spray Guide for Growing Stone Fruit at Home
I don’t think I’ve had blossom rot. NC State says Blossom blight is “caused by Monilinia fructicola that also causes brown rot on fruit”. So blossom blight and blossom rot are the same thing, yes? I didn’t see any of that last year, but to be honest, I was so busy working that I had very little time to monitor my orchard like I should have.
Read more at: Blossom Blight on Peaches | NC State Extension
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yay
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I spray for brown rot at pink, not for shoot blight but to tamp down how much brown rot is active in my orchard. If you don’t have big problems with brown rot you can probably skip it though.
Note it is really hot in the summer here and I don’t do the biweekly cover sprays; if I get ahead of the rot enough I don’t need those later sprays. A stitch in time save nine kind of thing…
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OK, that makes sense…
Last year was the first time I saw brown rot and scab on my peaches, and I don’t have a gauge for how bad it is compared to others.
If I do the early spray at pink, it is supposed to last for 21 days. How do I know if that initial spray took care of it, or if I need to do the later sprays… do I simply look and watch for signs of it starting, and if I see it, then put down another spray? Wouldn’t that be too late to stop it from spreading?
Do you have problems with brown rot in other stone fruits besides peaches?
Thanks!!
Neither Scott nor I can speak for KS- your weather is much different and brown rot is probably mostly a problem there when the rain doesn’t dial down in summer. Where we are it never dials down on a “normal” year. .
Here I have customers whose stonefruit gets sprayed with fungicide and oil when peach blossoms are showing some color and then at petal fall and again 10-14 days later and then one more mid summer fungicide spray. I have other ones that I forgo the earliest fungicide spray but receive the rest. I haven’t really noticed a difference in brown rot pressure between the two systems, but I generally have a good handle on it in either case.
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Just wanted to mention Infuse (propiconazole) is a locally systemic. For systemics, you generally want to wait till there is a decent amount of foliage on the trees.
You’ll notice the label on Infuse says, “Apply product to the point just when it begins to run off of the leaves.”
We are also at pink here (although it hit a sunny 77F today and brought out a lot of blooms). At pink, there aren’t any leaves.
You might consider a protective vs. a systemic, if you want to get an early handle on brown rot.
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I went back and read that. It mentions it several places on the label, but not under the ‘Bearing Fruit and Nut Trees’ section, so I missed it the first time.
I thought it was a little odd it didn’t specify at which growth stage to begin application. It only says “Start applications in early Spring”.
Both myclobutanil and captan would be considered ‘protective’ fungicides?
Myclo actually has some kickback against the fungus, which means it’s more than protective- it can kill existing fungus. It’s not just a matter of being impervious to rain- in penetrating the cells its treatment is deeper. But Myclo is much more affective on apple scab and CAR than brown rot. Indar works well on all of it but prop isn’t even labeled for pomes (or at least not listed as affective by Cornell). I wish Indar was available in homeowner packaging because someone with a small orchard shouldn’t have to make more tank mixes than necessary.
I recommend you use Chlorothalonil as an early treatment, especially for peach scab. However, it isn’t entirely compatible with oil so don’t include that in the mix, although last year I got away with it when spraying apples at bout half-inch green. I was treating peach leaf curl with the same tank. It all worked out fine but I learned of the incompatibility shortly after spraying- not a great testament to my competence but the info wasn’t on the labels.
I did learn (or believe I did) that PLC can be treated even after the trees show just a peak of green.
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As Alan mentions, myclobutanil is systemic. It’s a group 3 (DMI) fungicide, which is the same group as your propiconazole and Indar. What that means is that all DMI’s have the same mode of action (some just work better for certain fungal diseases than others). They are all systemic.
If you are going to use a fungicide this early, I’d also use the chlorothalonil. Like captan, it’s a protectant. I prefer it for early treatments on peaches vs. captan because it is a broader fungicide and tends to be highly effective for lots of different fungal diseases. As Tippy mentioned earlier, it can’t be used after shuck split.
At our orchard, we generally don’t spray anything before petal fall on peaches (except for a leaf curl spray, which we generally spray in late fall). But we generally stay really on top of diseases during the growing season, so perhaps we don’t have as much inoculum for blossom rot that we haven’t had to spray for it.
In the commercial formulations, but are the home use labels as restrictive? Not that I’d want to use it later.
Mark and Alan, thank for the explanations and information.
Figuring out which fungicides to use, their mode of action, and when to use them is more complicated than I thought it would be.
The only reason I was going to put the first spray down at pink, is because this KState bulletin recommends doing so.
Spray Guide for Growing Stone Fruit at Home
If it’s really not necessary, I will skip it and my first spray can be chlorothalonil at petal fall as you both suggested.
The chlorothalonil label I have states “Do not apply between fruit formation and harvest”, so its use is limited to the first spray.
From shuck split forward it sounds like the only one I can use that takes care of both brown rot AND peach scab is Captan. I made some notes from some discussions here I read, and I have jotted down that Myclobutanil is effective against scab, but it does not say that on the label.
So is there any advantage to adding Propiconazole or Myclobutanil to the tank with Captan in my later sprays? Or is Captan all I really need?
Chlorothalonil - Brown Rot, Blossom Blight, Scab (do not use after shuck split)
Propiconazole - Brown Rot, Blossom Blight
Myclobutanil - Brown Rot, Blossom Blight (not listed for scab)
Mix 1/3 fl. oz. of MONTEREY FUNGI-MAX™ BRAND with 1 gallon of
water and uniformly apply to all parts of the tree to point of runoff. For
brown rot blossom blight, brown rot, and powdery mildew, apply at early
pink bud stage (the tips of the petals are visible and the flowers are still
closed) before infection occurs. Reapply every 7 to 14 days so long as
disease symptoms persist
Captan - Brown Rot, Peach Scab