How to Successfully Get Rid of and Prevent Japanese Beetle Grubs

A portrait Japanese Beetle grub
A portrait Japanese Beetle grub

Japanese Beetle: two words that strike fear into the heart of every lawn-lover and gardener in the United States. 

Japanese Beetle grubs have become one of the biggest problems Minnesotans face each summer. Instead of living in fear of them, you can get to work by trying to control their massive population.  

Environmental Pest Management is here to help you successfully reduce Japanese Beetle Grub populations. They utilize integrated preventive measures along every stage of the beetle’s life cycle. 

When the bugs get to be too much, it’s time to call in the professionals. If you find yourself infested with pests like Japanese beetles, contact Environmental Pest Management. Your free consultation awaits!

Where to Begin? 

japanese beetle portrait

Treating your yard for beetle infestations can be a bit tricky. Like the infamous chicken and egg question, it’s hard to pinpoint where to start. Let’s begin! 


First, be aware of what creature you are up against. The predator that strips plants to the bone and leaves lawns aghast is a creature no bigger than your fingernail. 

The beetle’s shells have a shimmery-green head and rust-colored wings. Deceptively mundane looking, they can be highly destructive. You can see evidence of its presence from early Spring to late Fall. 

Life Cycle

Photo courtesy of Japanese Beetle Management in Minnesota, University of Minnesota

Once identified, it’s helpful to know the Japanese beetle’s entire life cycle from start to finish. 

During the summer mating season, female Japanese beetles can lay eggs. They can lay up to 60 at a time into the soil. This process can happen anywhere from July-September when adult beetles emerge. 

After the eggs hatch, they become grubs. The grubs quickly grow, and white grubs feed on the root systems of lawns and gardens, creating turf damage. Homeowners will commonly see spotty dead spots and patches on lawns

Once grubs have formed and begun their harmful eating, they essentially go through a two-staged process before emerging into adults. The first grub stage is in the Fall when they are new grubs. 

When temperatures begin to drop, the grubs will then burrow deep underground and lay dormant through the winter months. 

The second grub stage begins after the ground thaws. Destruction begins when these slightly more mature grubs viciously feed on root systems in lawns once again.  

After this, the mature grub then begins its metamorphosis into the pupa. Quickly after that, the adult beetle emerges, wreaking havoc on just about every edible plant around. Mating happens, and the process begins all over again. 

Countless plants are susceptible to beetle damage. Gardeners will notice the almost immediate destruction of roses, raspberries, apple trees, beans, and other plants; all brought about by adult beetles. 

The entire life cycle process from start to finish goes largely unnoticed until it’s too late. 

Don’t be discouraged! With Environmental Pest Management here to help, there is still time to disrupt and kill the pests during any stage of their life cycle. 

Japanese Beetle Reduction Process

A Japanese Beetle on a leaf

Even though it takes an entire year or more, the whole life cycle of the Japanese beetle from start to finish is quite simple. However, the means to eradicate them can get a bit tricky. 

Timing is everything. 

Once again, the chicken/egg problem emerges. Thankfully, prevention can start at virtually any stage of its life cycle. As long as it is continued and maintained, beetle population reduction is possible. 

For this example, we will go through the stages starting at the second grub stage when ground thaw occurs in the Spring. 

Spring Grub Stage 

Grub control products for lawn care are found at many home and garden stores. Most of these are chemical-based except for Milky Spore and Neem oils. 

Milky Spore is a natural product that can provide benefits. Even though the product claims to provide lawn assistance, unfortunately, no science currently backs its success. 

Adult Stage

A shiny Japanese Beetle in the adult stage

The next stage to attempt population reduction is the adult stage. This happens in early to mid-July when adults emerge from the ground. Their destructive presence is unmistakable. Gardeners across the US want them as far away from plants as possible. 

Using Japanese beetle traps is an easy and effective option. These contain pheromones which produce an attractive scent the beetle follows right into the well-designed trap. 

It’s best to place the traps in multiple locations around your yard. Traps can fill quickly, so you will want to make sure you have backups as well. 

There are also protective products you can put on your plants to kill or deter the beetles. Conventional and organic options are available at most stores. However, if you have the time, the absolute best option is to hand-pick them off into a bucket of soapy water. 

Breeding and Egg-Laying Stage

Once the egg stage begins, control measures get slightly more advanced. Popular insecticides work well for turf, but they will need re-application after any rainfall. This can get time-consuming for homeowners trying to keep up with endless to-do lists. 

Fall Grub Stage 

Finally, in our example, we reach the fall primary grub stage. Treatment is the same as spring mature grub control. You can apply more granular grub control products from late August into early November or until the ground freezes. 

Prevention is Possible! 

A pest control specialist spray a lawn to help prevent Japanese Beetle grubs

Though it can be challenging, controlling the Japanese beetle population is possible. It takes proper timing, dedication, and persistence. Prevention is always best when it comes to any pest type. 

Knowing your enemy and the ways to combat them are great tools to have in your arsenal. Sometimes even the best defense is no match for the plethora of Japanese beetles. 

When the bugs get to be too much, it’s time to call in the professionals! If you are struggling with your Japanese beetle population, contact the experts at Environmental Pest Management. 

Minnesotans only get a few months to relish, don’t waste yours battling a never-ending enemy. Don’t let Japanese beetles ruin any more of your yard or precious ornamentals. 

Contact us at Environmental Pest Management for a free quote today! Let us help you have a stress-free and Japanese beetle-free summer!

Japanese Beetles and What You Need to Know

Japanese Beetle eating raspberry leaves
Japanese Beetle eating raspberry leaves

You have likely seen these annoying pests, whether or not you knew the name. These flying beetles with green bodies and brown wings seem to invade when the weather gets warm, and plants are blooming.

But what do you do if you see these insects destroying your plants and eating everything in your garden? Before buying Japanese beetle traps, speak with a pro. Environmental Pest Management is here to help rid you of pests around your home, whether they be inside or out. Check us out for a free quote today!

Japanese beetle

Japanese Beetle Facts

Japanese beetles are relatively easy to spot. As an adult has a body that is a metallic green color with brownish, almost copper, wings.

These beetles can’t resist your plants, especially ones growing in the warm sunshine. They will descend upon your yard and devour sweet-smelling fauna.

Certain plants are more attractive, like apple and black walnut trees, or plums and grapes. It is hard to miss their work. Your once luscious yard might take on the look of a haunted patch. Japanese beetles eat the flesh of plants, leaving skeletons behind.

Thankfully, Japanese beetles prefer to be outside in the fresh air and don’t often enter homes. That doesn’t mean you will never see a stray that accidentally slipped inside, though.

Just because they aren’t inside doesn’t mean you want them on your property. Anyone with a green thumb will take particular offense to the presence of these pests. Even if you don’t consider yourself a gardener, you likely enjoy your green yard and don’t want to see the wreckage of the plants left behind.

A pressing problem with Japanese beetles is that some years there seems to be a surge in population. You might go a year or two and hardly notice them, and then the next year your yard is destroyed by a vast number.

There are four stages to the life cycle of a Japanese Beetle.

  1. Eggs- The eggs are small and white, and shaped like an oval.
  2. Larvae- These white grubs are incredibly damaging to yards.
  3. Pupae- This stage is where the transformation to a full-grown beetle takes place.
  4. Adult- The adult beetle is no more than ½ inch long and lives for up to 50 days.

To reproduce, Japanese beetles dig small holes or burrows in the ground.  A female will lay anywhere from 40 to 60 eggs throughout her lifetime. Larvae are called grubs, and they eat roots and other food in the soil leading up to winter, then are dormant during cold months.

When the weather warms up, the grubs wake up and begin eating and growing. In the late spring and summer, adults dig out of the ground to mate. Of course, this is when they attack your yard, as well.

Japanese Beetle on leaf

Japanese Beetle Behavior

Japanese beetles likely originated in Japan, hence the name. They were first found in the United States on the East Coast in the early 20th century. A common belief is that they arrived on our shores through trade and other forms of commerce.

As previously mentioned, they thrive in areas with plentiful vegetation. Whether you have a lush, green lawn, and vegetable garden, a fruit orchard, or just abundant trees, Japenese beetles will likely find your yard.

Japanese beetles are considered transient, meaning they rarely stay in one place. They can travel miles, depending on wind and availability of food. They tend to stay close to areas with an abundance of food, however.

You are most likely to notice these hungry pests in the early summer when the weather is getting nice and warm, and your plants are most fragrant. They peak anywhere from late June to early September. The colder temperatures of the fall will begin to kill them off, however.

japanese beetle flying

How to Get Rid of Japanese Beetles

Because Japanese beetles are dangerous at both the larvae, or grub, and adult stage, it is essential to fight them on both fronts. You will likely need to utilize a variety of methods to effectively exterminate a population of Japanese beetles in your yard and keep them out.

You will want to be on the lookout for signs of Japanese beetles and be taking steps to prevent them. Japanese beetles can travel miles, as previously mentioned, so you might not realize you have a problem until they have done a bit of damage.

The first critical step is to apply a soil insecticide at the correct time. Besides treating your soil to prevent grubs from thriving, you will want to make changes to your yard to prevent Japanese beetles from settling. 

Replacing plants and trees they are attracted to with strands they stay away from is an excellent way to keep these pests out of your yard. If they don’t want the food, they won’t settle as your um-wanted neighbors.

If you physically see Japanese beetles in your yard, attack them when they are at their weakest, i.e., early morning. These beetles are sluggish and lazy in the early morning hours. Taking a few minutes to shake the branches of the trees they are in and catching the falling beetles in buckets of water will take care of a good part of the population.

Japanese beetle traps use pheromones to attract the beetles and then kill them. The problem here is that the traps do their job, attract beetles. This likely means you will end up with more Japanese beetles in your yard than before.

If you prefer using chemicals, there are a variety of products aimed specifically for Japanese beetles. A quick trip to your local nursery will yield you a variety of results. As always, be extremely cautious using any chemicals and ensure you read the entire label before use.

A close-up of a small Japanese beetle standing alone on a green leafy plant

Call the Professionals at Environmental Pest Management

If you have noticed Japanese beetles in your yard, give us a call at Environmental Pest Management. We will tackle the problem on all fronts, ensuring that the larvae and adult stages are addressed. Unlike Japanese beetle traps, we won’t attract more pests to your yard.

We are aware that families, along with their kids and dogs, live in homes, and ensure we use safe methods. We have families of our own and only use products and practices that we would use around our own homes. You can feel safe letting us into your home and yard.

Don’t tackle this problem alone! Let the experts at Environmental Pest Management help.