One of the worst pests for many gardeners, there’s no doubt that Japanese beetles are very destructive! They can cause major damage in the garden, and can be difficult to control.
If you have them in your garden, then this post is for you! Below you will find tons of tips for controlling Japanese beetles in your garden – organically!
Theeeeey’re heeeeeere… They are nasty bugs, and their sole purpose in life it to decimate your beloved plants. They are Japanese Beetles.
Ok, ok, I’m being a little overly dramatic here. I’m sure that technically Japanese beetles have some other purpose in the circle of life… but it doesn’t seem like it.
During the course of a summer, I see thousands of Japanese beetles in my garden. Thousands! They are out of control.
What Are Japanese Beetles?
I remember the first time I saw a Japanese beetle in my garden. I actually thought it was kinda pretty. But over the course of 2-3 years, the population exploded and they quickly became a HUGE pest here in Minnesota.
Adult Japanese beetles damage plants by eating holes in the leaves and flowers, and quickly skeletonize the foliage. They can decimate a small plant in a short time.
During mid to late summer, Japanese beetles are everywhere, and it’s hard to miss them. The adult beetles are oval with an iridescent brown/green body, and they are 2-3 times the size of a lady bug. The can fly, and are usually very active during the day.
The lifespan of an adult Japanese beetle isn’t very long, adults are usually present for less than two months. The beetles lay eggs in the soil, and the larvae (aka: grubs) hibernate deep underground during the winter.
This extremely destructive pest can do double damage. Not only are the adults a huge pest, but the larvae is too. Japanese beetles larvae are grub worms, which feeds on the roots of lawns and other grasses.
What Do Japanese Beetles Eat?
The plants that Japanese beetles seem to love the most in my garden (and therefore do the most damage to) are roses, hibiscus, zinnias, canna lilies, grapevines, beans, and my poor linden tree.
But there are lots of other plants Japanese beetles will feed on too.
In my garden, I’ve also found them feeding on coneflowers, squash, peas, and a few other plants here and there.
How To Control Japanese Beetles Organically
The key to controlling Japanese beetles organically is to stay on top of the problem. Once I start to see beetles on my plants, I get to work immediately. I try to get out in the gardens at least once a day to do damage control.
The best way to deal with the adult Japanese beetle is to hand pick them off the plants, and drop them into a bucket of soapy water to kill them.
Gross, I know! But don’t worry, you’ll get used to it.
By the way, don’t just use water in your bucket, make sure to put soap in there too. The soap will kill the Japanese beetles quickly.
Otherwise, they can swim for a really, really long time – like days. It’s creepy! And disgusting.
I’ve tried a few different types of soap in my bucket, and I love Dr. Bronner’s Baby Mild liquid soap the best. It kills the beetles faster than other soaps I have used, which means there’s no way any of them will escape my bucket!
The best time to hand pick Japanese beetles is early in the morning, or in the evening.
Japanese beetles aren’t as active during these times of the day, so less of them will escape my wrath. Plus, I can’t stand doing it during the day when they’re buzzing around and flying at me – EEK!
How To Hand Pick Japanese Beetles
Hand picking the Japanese beetles sounds easier than it is because sometimes they hold on tight to the plant and won’t let go.
Either that, or they will drop off the plant as soon as you disturb it, so you have to be quick with the bucket. And don’t stand directly under the beetles either… just trust me on this one (that’s a story for another day).
I find it easier to clip off the leaf or flower they’re munching on and drop the whole thing into the bucket, bugs and all.
To make it a bit easier to hand pick the beetles, you can spray them with soapy water first.
The soap will kill some of the Japanese beetles on contact, and the rest will be stunned and easier to drop into your bucket.
I use Dr. Bronner’s Baby Mild liquid soap for all of my organic garden pest control, it works really well.
It’s a bit of work to pick off the Japanese beetles and drop them into a bucket of soapy water, but it’s easy enough that pesticides aren’t necessary… and it’s sooooo satisfying.
More Tips For Controlling Japanese Beetles
Hand picking the adult beetles is just one of the ways I control Japanese beetles in my garden. Here are a few other ways that will help you fight them in your garden organically…
- Beneficial nematodes are a natural way of controlling grub worms in the soil (aka: Japanese beetle larvae). Beneficial nematodes are tiny organisms that feed on grubs, and kill them before they can emerge as adults.
- Pheromone traps are another great option for controlling the adult beetles without spraying harmful pesticides. Read more about how to use Japanese beetle traps in your garden.
- Spray an organic insecticidal soap directly on the adult beetles to kill them. I mix my own using 1 tsp of Dr. Bronner’s Baby Mild liquid soap with 1 liter of water.
- Sprinkle the adult beetles with diatomaceous earth to kill them. Diatomaceous earth gets under their shells, and as they move around it cuts them up, and eventually kills them (sounds bad I know, but it’s way better than using chemicals!).
- Neem oil is a natural, plant based pesticide that helps to deter bugs from feeding on your plants. Horticultural oil also works great.
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More About Organic Garden Pest Control
- How to Control Squash Bugs Organically
- How to Get Rid of Squash Borers Organically
- Beneficial Nematodes As Organic Pest Control
- How To Control Flea Beetles In The Organic Garden
- Using Eggshells As Organic Pest Control
Leave a comment below and tell us how do you control Japanese beetles in your garden organically.