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How To Make Japanese Beetle Spray – A Simple, All-Natural Recipe To Protect Plants!

One of the best ways to protect your flowers, shrubs and bushes from Japanese beetles is to make your very own homemade organic beetle spray. Not only is it easy and fairly inexpensive to make – it works like a charm to keep beetles from devouring your plants.

Japanese Beetles can cause a lot of damage to plants. And, in a very short amount of time! Here in Ohio, beetles usually begin to appear the first week or two of July. What starts as a trickle of beetles can suddenly turns into a full blown beetle invasion. All within a matter of days.

Unfortunately, if you are not ready for them, they can decimate plants quickly. Even worse, when left unchecked, they will double or triple their population in the blink of an eye. And not just for this year, but for the new wave of beetles that will come next year.

spraying for Japanese Beetles
Japanese beetles can quickly destroy the foliage of plants with their massive appetite. If no action is taken, they can all but wipe out perennials, annuals and more.
The Life Of A Japanese Beetle – How To Make Japanese Beetle Spray

Japanese beetle grubs overwinter and live in the soil. When the beetles come out and feed on your plants, their main purpose is to reproduce. After which, the females lay eggs back into the soil. Those eggs then hatch in late summer to become grubs.

For the remainder of the summer, the grubs feed on the roots of plants underground. That can also cause damage to lawns in the form of brown spots. As fall settles in and winter approaches, they dig down deep into the soil to protect themselves from winter’s chill.

Unfortunately, the more beetles you allow this year to live, mate and deposit eggs in the soil – the more grubs and eventual beetles you will have next year. All the more reason of course to take care of them now!

An All Natural Approach – How To Make Japanese Beetle Spray

We are adamant about keeping a chemical free setting at our farm. Not just because of safety or potential health hazards from commercial products, but also because spraying insecticides can actually create even more pest problems for our plants, trees and bushes down the road.

Although insecticides can be effective in killing off beetles, we simply don’t want chemicals touching anything that we will ever eat – period. But beyond that, they simply cause more harm than good.

pollinators and beetles
Insecticides are non-discriminatory, and will kill the insects that pollinate plants as well as the beetles that destroy it.

Insecticides are non-discriminatory. That means they also kill off a huge population of beneficial bugs and pollinators while killing off the beetles. And when there are less bees and butterflies flying around, that means few chances to pollinate your flowers and vegetable plants.

In addition, when a large portion of insects disappear, the normal balance of nature can be completely altered. The result can be a whole new slew problems from insects that were being kept in check by all of those beneficial insects that have been wiped out.

A Two Prong Approach To Beetle Control – How To Make Japanese Beetle Spray

For us, we approach keeping our plants safe from Japanese beetles with a simple two prong approach. The first is simply hand picking beetles off of plants as they arrive.

You would be amazed how quickly hand picking can reduce the beetle population. Heading out in the late morning and brushing them into a bucket of soapy water results in less beetles to mate, and to lay more eggs to become grubs. A few weeks of daily hand picking can and does work!

But to protect our plants in between, we use a secondary approach of an all natural repellent spray made from cedar oil. Together, over time, the two methods have worked wonders to control Japanese beetles for us. In fact, at our old farm, they were all but non-existent the last few years before we moved.

Now that we are at our new farm, we find ourselves dealing with them again. And once again, we are employing hand picking and the cedar spray to take care of the problem. The good news is the recipe is easy to follow and the spray is easy to make. Even better, it really does work incredibly well to flush them from plants – and keep them from coming back!

All Natural Japanese Beetle Spray Recipe

Ceder oil is effective as a repellent against Japanese beetles. It will not kill the beetles, but they certainly do not like it in the least. In fact, when it is sprayed when they are on a plant, they leave fast. And if it’s already on the plant – they will stay away, protecting the foliage in the process.

You can make homemade cedar oil spray using a couple of different methods. If you happen to have access to a few cedar boards, you can make the spray simply by soaking the boards in water. If not, you can also make it using pure Eastern cedar oil mixed with water. Here is a look at how to make the spray mix using either method:

Making Cedar Spray With Wood Chunks – How To Make Japanese Beetle Spray

To make your spray using Eastern Red Cedar wood, you will need six to eight small pieces (approx. 4″ long x 2″ wide) of wood. The real key is to keep the chunks of wood small enough to fit down into a 5 gallon bucket.

As for where to find Eastern Red Cedar boards, your best bet is a local lumber yard unless you are lucky enough to have them growing in your backyard!

Place the chunks down into an empty 5 gallon bucket. Next, fill the bucket with hot water. We heat a large pot of water over the stove until it boils, and then carefully fill the bucket. The hot oil helps to release the oils in the cedar.

Eastern Red Cedar
Eastern red cedar is the perfect wood for creating an all-natural spray to repel Japanese beetles. The beetles do not like the scent, and will stay clear of plants that have been sprayed with it.

Once the water has been placed into the bucket, let it sit and soak for three to four days. To keep the cedar wood from floating to the top, place a brick or heavy item on top. We stir our bucket a few times each day to help release more oil.

After the boards have had time to soak, pull out the boards and strain the water to remove any loose particles. Your homemade cedar spray is now ready to use!

Making Cedar Spray With Cedar Oil – How To Make Japanese Beetle Spray

You can also create an effective cedar spray using pure Eastern Cedar oil. Although it tends to be a bit more expensive than making it with boards, it is certainly a little faster and easier to make. Product Link : Eastern Red Cedar Oil

For creating spray mix with oil, use 1.5 tablespoons of cedar oil for every 1 gallon of water. Since the oil is already in its purest form, there is no need to heat the water. Just mix thoroughly and you are ready to spray!

How To Spray To Control Beetles – How To Make Japanese Beetle Spray

The best way to apply the spray mix is with a pump sprayer. For smaller areas you can use a spray bottle. Before spraying, add in a few drops of olive oil or mild liquid dish soap to the solution. This will help the spray stick to the foliage and give better results.

pure cedar oil
You can use cedar oil in place of cedar boards to make homemade Japanese Beetle spray.

Apply the spray liberally to the leaves of any plants the beetles like to attack. If the beetles happen to be on the plant, it will have them quickly leaving. As the mix dries on the foliage, the scent will also keep future beetles from landing on the plants as well.

You will need to reapply the spray often to keep its effectiveness – especially after any rain or heavy morning dew. We usually spray plants every two to three days for the few weeks the beetles are most active.

Here is to protecting your plants from Japanese Beetles this year – and for years to come as well! Happy Gardening, Jim and Mary.

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