Japanese Beetle Summer Spraying Recipe

Tom Wahl at Red Fern Farm told me his organic recipe that he states is the best control he’s come up with.

Dyna-gro neem oil 1 ounce to either a half ounce or 1 ounce of dish soap. If temps are cool use 1 ounce of dish soap. If warmer temperatures use 1/2 ounce dish soap. Dish soap being your surfactant.

Dyna-grow is 100% concentrated neem oil whereas others are 40% concentrate.

If you’re new to spraying, fill your tank with the necessary water first. Then, add the oil and dish soap. Put the lid on, shake your tank, and spray. It’s good to shake/agitate your tank as you go from tree to tree.



I started using neem a few years ago only because it was what was in my sprayer at the time. They were all in my rose bushes. A few pumps of the sprayer and they couldn’t get away fast enough. I mix in surround to the mixture now but I thinks most of the work is done by the neem.

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Hey Dax, do you use this DynaGro neem recipe?
I don’t have Japanese beetles yet, but the May/June beetles and Chaffer beetles are eating a ton of foliage on my brambles and some fruit trees. Something started eating my newly forming grapes, I think that is beetles as well, but not positive. I just ran out of spinosad and need to order more, so was thinking of trying the neem as well. @Auburn, are you still keeping beetles under control with neem?
Thank you for any input you might share.

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I’m assuming the recipe is oz / Gal

I may give it a try. I’m skeptical of how when it would work with the heavy JB pressure I have here.

Neem still helps but it is not a total control.


I got the recipe last Fall so no I haven’t used it. I have basic Neem (40%) and that label says it will not kill Japanese beetles. I would put all my trust in Tom Wahl at Red Fern Farm. I spent a lot of time walking, talking, and looking at trees and discussing other trees/insects/disease.


Well, I am game to try and see how it works.:grinning: Thank you!

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Saw my first J Beetle yesterday. They have arrive TN/KY.

I just noticed this note. I’m wondering if anyone has tried using this on J. Beetles. I’m highly skeptical of second hand advice not supported by any research.

Any material sold for J.B. control has been researched for actual efficacy. The nature of this pest could easily lead to anecdotal misinformation because they come and go unpredictably.

I sprayed neem on them multiple days in a row on my fig tree, I even sprayed right in the mouth of those latched down on figs they didnt even budge. I had to spray them with seven and away they went.
Didnt bother to eat any of the figs that year.

I’m going to have to double post this here and here: What did I do wrong? (spraying apples with neem)

Tom Wahl writes:

“I have read of neem oil being able to kill some insects, but I have never witnessed it myself. From what I have seen, it is an effective repellent against insect pests without harming non-pest insects. If I spray in on plums, grapes, and hazels just before the Japanese beetles arrive in mid/late June, they stay away. If I reapply it within two weeks, they keep on staying away. On the other hand, if I wait until the beetles show up and then apply neem, the beetles will fly away immediately (not die), but a few will start coming back after several days. Neem does not keep 100% of plum curculio away from plums and cherries (and it only takes one to ruin the fruit). I have not had much curculio problem on apples, probably because I have enough plums and cherries they feel no need to go to apples. Neem does seem to keep away apple maggots and coddling moth, which, for me, are more of a problem on apples. It is also effective at controlling cedar/apple rust and apple scab. The bottom line is that neem is great for most apple diseases and pests, but don’t count on it for curculio. FYI, there are a lot of products out there with neem oil cut with additives like surfactants and fillers. I don’t know how well they work. The neem I am talking about is 100% pure neem oil. One oz. oil plus one oz. dish soap to one gallon of water.”


Thank you for posting this. I was looking at using neem oil as one of my fruit tree sprays. I have a couple of other Bonide sprays I will be using but I can only use them a few times per the instructions from Bonide company. I will look for the 100% neem oil to use. Great info.

Almost every morning I walk through my garden/orchard looking for Japanese Beetles. I carry a small pump up bottle (34 oz) of water mixed with different additives. Water/2 tablespoons neem appears to aggravate but not kill the beetles. Then I used water/neem/1 tablespoon of dish detergent. I sprayed a few beetles and displayed them to check the effect. After about 15 minutes they were dead. Then I just used the water/dish detergent and this also killed the Japanese Beetles. Lately I have been using water/3 tablespoons of Safer Soap and this also killed the Japanese Beetles and appears to be gentler on the foliage. All these sprays were only used as spot sprays and I don’t know how well it would work if the entire plant was sprayed.