Thanks JoeReal for sharing the recipe! I found this to curb the leaf curl to virtually nothing on my suncrest as well as frost peach! Compost tea could be a good idea but the probiotics comparison is not a goodone (recent studies show decreased gut flora biodiversity following pro biotics after antibiotics vs nothing) so if your compost has a very diverse mix of microbes it could be good if not not so much
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Just like the microbes being missing from the leaf surface ācanā allow the bad microbes to colonize, the same can happen in your gut. Biodiversity ācouldā be good or ābadā microbes. Biodiversity just means a lot of types, not that they are all good for you. Probiotics are helpful āgoodā microbes. The biodiversity will increase quickly without allowing the bad ones an early foothold. Just my 2 cents.
I should have clarified that the compost tea is not just āmy compost mixed with waterā.
I use my high quality organic permaculture compost, local organic dairy-doo, worm castings, fish hydrolysate, kelp meal, green sand, rock phosphate, azomite, Em1 and organic molasses. Not just a diverse mix, but a ācorrectā diverse mix all highly aerated for 24 to 36 hours and sprayed immediately afterwards to insure minimal die off of microbes before they are applied.
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Neem oil works great on PLC as a solo act. Also great for killing black spot, mildew, and a broad range of pests & beneficial insects. It has a distinctive aroma like citronella, but kinda sharp & sour. It seems to last 7- 10 days depending on rains.
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Iām not a fan of neem spray, I spent a lot of $$ and time and then watching it not help with various issues. Its fine for aphids and mildew but I donāt know much else. Painted on to trunk bases it also does well against borers (at full strength). Maybe out west it can help more but in the east it is not the cure-all claimed.
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Thatās what I use it for here on the Left Coast. It also helps with apple scab, which isnāt a a big problem here except on very susceptible varieties. I havenāt found it effective for PLC in my environment, though.
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What neem are you using?
Any good neem needs to be highly saponified (hard and clumpy under 80F) and should be mixed with a good organic surfactant first in warm water. I find most people who have not had success with neem were not using a first cold pressed neem oil and neem oils not from india which have not been processed correctly. Any neem that is liquid in the bottle under 80f is junk imo. Its like comparing actual cold pressed olive oil with canola oil. One is amazing drizzled on tomatoes and works great.
Usually its sulphonated canola or corn oil added to the surfactant that gives it more anti fungal / bacterial properties.
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When I was spraying it I used neem from neemresource.com which is supposed to be the good kind; I had to warm it up to get it liquid if it was cooler temps. It took me awhile to get it into solution, first I tried Dr Bronners (sic) soap and that just made a mess of my sprayer. Regular dish soap did the trick.
Anyway it didnāt do much to help with the various problems I had ā¦ no good for my climate except for borers on the peach trunks.
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Ah well that is great neem for sure. What i personally have found that really makes the difference with neem however it really is very important what surfactant you use so that it is able to disperse and spread the neem oil evenly (Also a good sprayer and washing it out with warm soapy water is a must for neem on tools). All neem really does on its own is the IGR stopping the bugs from molting and disrupting there breeding cycle, It really needs a good surfactant to dry out the bugs as well and usually another vegetable oil to help smother insects and mildews/molds as well as something anti bacterial for diseases. Its also very important when spraying to hit all Target and host plants because your real goal is to disrupt there mating cycle and if the grass and other trees are sheltering the insects that will come right back to your fruit trees its probably not that effective. Applying another oil based product alongside neem or adding a sticker would help those in more humid climates.
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Iāll let someone else try, I did enough time on it myself. My feeling is neem is not a particularly good mid-atlantic spray, there is too much rain, heat and humidity feeding the bad guys out here. In the west or north maybe, but not where I am.
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Totally makes sense. I just feel like there is a lack of knowledge out there on organic pest control and like to try and help spread good sustainable farming techniques to any who want them. I dont think neem is something anyone should focus on for fungal diseases but i do think its a great part of a integrated IPM program.
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I believe its the reaction between the hydrogen peroxide and the vinegar in this recipe that is the main driver of resultsā¦ the oil is just a secondary
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Sounds like something I should try out next year.
Iām excited to try this recipe, and love the idea of not adding copper to the soil. I have three questions, please:
- In your recipe you say āSpray during bud swellā¦ā which sounds like a single application, but in your reply from May '18 you say āwe spray after leaf fall, middle of winter and budswellā, three applications. Am I correct in understanding that you do recommend three applications? (Iām in Menlo Park, CA)
- Is it important to do the spraying only when the weather forecast calls for several no-rain days following?
- My plums and pluots had some Leaf Curl Plum aphids this past year, and Iām wondering whether I could/should just use the same Italian Dressing recipe for them. It would be nice to only have to mix one thing for both sets of trees. If the answer is āyesā, should I also apply it three times?
To prevent aphids, apply dormant oil, for example, see this article: Homemade Dormant Oil Spray for Fruit Trees | Home Guides | SF Gate. Aphids are a plum/pluot problem (mostly), and PLC is a peach problem, so these are two separate sprays. Also, when peaches are at bud swell, many plums/pluots are already blooming/leafing out, hence timing of these two sprays is different.
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Thank you JoeReal, for this fascinating idea of in-place chemical reaction, to make peracetic acid.
Iāve had a lot of trouble with Curl and this year I tried to be more on top of it. Here in Southern California some early peach varieties can bloom 1st week of January, so the spray window is pretty small. First I stripped the leaves off the peach trees [they donāt fall off early enough] and sprayed early in December, using Liqui-Cop and vegetable oil. Few days ago I wanted to spray the H2O2 and vinegar, separate sprayers. But as I was recalculating what proportions I had to use, I had a sense that the two mixtures were not at all in balance.
So I want to ask, since the peroxide solution is 0.5%, and the reaction involves equal molecular amounts of vinegar and peroxide -
[Peracetic acid - Wikipedia]
H2O2 + CH3CO2H ? CH3CO3H + H2O
then shouldnāt the vinegar solution also be about 0.5%?
If you add 2 oz of 5% acetic acid to 132 oz of water (1 gallon), I calculate 2/134 * 5% = 0.075%. So I wondered whether perhaps where it read 2 ozs a typo occurred. Can you revisit how you decided on the dilutions to be made?
I went ahead and used a stronger vinegar solution. Itās a bit tricky seeing, by the light of a headlamp, where the 2nd spray has covered as the bark is already wet from the first spray! Thereās no visible damage from the sprays.
Thanks again for an excellent contribution.
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@JoeReal hasnāt been around here since last summer so you might not get a replyā¦ my guess is the proportions are not needing to be exact but it wouldnāt hurt to bump up the vinegar. For dormant sprays you have little worry of damageā¦ just donāt let the aqua regia loose on it!
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Is the recommendation for the amount of Dawn to use for the Italian Dressing Recipe based on original Dawn, or on Ultra Dawn (which claims to be 3-times as strong as regular Dawn)? I can only find Ultra Dawn at the store, so Iām wondering if I should use 1/3 as much.
Donāt know that it matters the soap is just ti keep the oils emulsified in solution, i dont use dawn just whatever dishsoap i have at the time
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Sorry to revive such an old thread, but I thought this would be the most appropriate place to comment.
3 years ago I experimented with controlling leaf curl by covering one of my dwarf peach trees in late winter with a plastic ātentā until the leaves were almost fully formed. The idea was to stop rain droplets splashing the spores off the bark and onto new, emerging leaves and so to break the infection cycle. Two nearby tress were sprayed with copper in late winter
That year there was leaf curl on about 3 leaves of the covered tree. They turned out to be underneath a small hole in the plastic. The uncovered trees 2 and 3 metres away had significant leaf curl, despite having been sprayed.
Next year I covered two of the trees (no spraying) and sprayed the third. Same result, except for a branch which protruded past the ātentā on one of the trees, which suffered significant leaf curl.
I now only spray trees that are too large to cover and donāt have natural resistance.
Has anyone else has a similar experience? I asked a leading horticultural university here in NZ for their opinion about my experiment and whether it had been tried in a more scientific fashion and on a larger scale, but received only muted interest
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growing peach trees under cover is a a common treatment in the coastal northwest US (similar climate to much of NZ). see this guyās blog for example:
this winter Iām using ziram, lime sulfur, and kocide 3000 (sorry for mentioning ziram in the organic thread but itās basically the cure-all here). hereās our local extension guide for peach leaf curl:
and a local test of kocide vs. ziram:
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