How to Kill Japanese Beetles Organically

It’s that time of year, unfortunately. The Japanese Beetles are out. And this year, I have more of them than I’ve ever had. They’re all over my grapes and asparagus and moving in to my raspberries. I’ve even found a couple on my snap beans and okra across the yard. It’s time to fight! But chemical pesticides are not an option for me, so here’s what I’m doing.

The past couple of years, I’ve caught the beetles early enough to stave off an infestation. Somehow, this year, my timing was off and I’m dealing with dozens of these nasty buggers.


The best preventative is having healthy plants. As with all pests, unhealthy plants are tastier to them. They will eat the entire leaf and leave the veins, making the plant look like a piece of lace (and not the pretty kind).

My grapes continue to struggle with health, regardless of how I feed them. As you can see, they’ve been on the beetles’ menu as a main course.

Japanese Beetle damage on a Concord grape vine

Japanese Beetle damage on a Concord grape vine

My raspberries are healthier. Although there is some damage, it isn’t quite as bad as on the grape vines – just a few leaves, here and there.

Japanese Beetle damage on raspberries

Japanese Beetle damage on raspberries

Japanese Beetle damage on raspberries

Japanese Beetle damage on raspberries

Unfortunately, grapes, asparagus, raspberries, and apples (though I haven’t seen any on my apple trees so far) are some of their favorite food. I’m not willing to give up my garden because of these pests, so I’m fighting.


It is very important to determine when Japanese Beetles first appear in your zone. Here, it’s around the end of May. If you have not had an infestation in the prior year, the first beetles you see will be scouts. (Otherwise, the first ones you see are probably the mature beetles from eggs laid last year.) The scouts come to check out your garden and scent mark it for others if they find something good to eat. These are the beetles you need to kill before they have a chance to “phone home” and bring the clan.

Take a bucket and fill it halfway with water and about a quarter cup of dish soap. Brush the beetles into the water to kill them. Then, leave the bucket near the plants you saw the most beetles on. This is important. The dead beetles will actually give off a scent that warns other beetles your yard is not a very hospitable place.

Continue to kill any beetles you see this way.

If you don’t catch them in time (as I, obviously, did not this year), you will have dozens of beetles to contend with. I found several of them mating on my grape vines the other day! (In the background of the picture below, you can see my Garden Wilson heading over to interrupt their liaison, bucket in hand.)

Japanese Beetle sex

Japanese Beetle sex


At this point, I’m long past finding the scouts. I’m now killing them in three ways:

  • Hand picking them/flicking them into the soapy water bucket. This is the most effective. I’m still leaving the bucket nearby, of course – in case.
Japanese Beetles - dead in bucket of soapy water

Japanese Beetles – dead in bucket of soapy water

  • Insecticidal soap – You have to spray them directly for this to be effective.
  • Neem oil – This is my next weapon, this weekend. I’ll spray the leaves with neem to deter feeding and reduce the population. (Take away their preferred food supply, basically.)


The Japanese Beetle grubs survive in the soil by eating roots, then mature the following year. They don’t send scouts; they just hop onto your garden smorgasbord.

I’ve learned that an application of granulated milky spore onto your yard and garden is effective in killing the grubs. According to research I’ve done, in hot areas (like the South), application should be done three years in a row. In cooler areas, it may take five consecutive years’ of application. However, once applied, it stays in the soil for years. The grubs eat it and are killed. It is not harmful to food crops or your lawn.

There’s also a particular nematode that can be applied to your soil that will work with the milky spore to kill the grubs.

The battle is on, folks! Me against the Japanese Beetles. I WILL win! My garden is at stake.

Are you fighting Japanese Beetles? What has been successful for you?


4 comments on “How to Kill Japanese Beetles Organically

  1. I have always had them attack my pole beans – to the point where I have now quit planting them and stick with the bush varieties! They also enjoy me crab apple trees. Oddly enough, this is the first year I have not planted any pole beans, and I haven’t had any on my crab apple trees either! I’ve only used the soapy water technique for them, and I still lose the battle 😉 The other thing we did this past year was mix up the soil really well and let our chickens (we don’t have them anymore, though) eat the grubs to their heart’s content 🙂

    • Wow…pole beans. Who knew? But, they really will eat anything, not just their favorites. I don’t have chickens (yet), but I plan to order some milky spore this weekend, to get any grubs that might be in the ground around their favorite food.

      I hate those things.

  2. Have to save this post along with your recent tomato post… We’re starting a new farm, so this is our first year here and haven’t seen any beetles… yet. They were a problem in our previous locale.

    FYI, I’ll be at Adat Shalom today telling about recent trip to Israel. If you don’t have plans, would love to meet you!

    Shabbat shalom!

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