Among the pests that attack and destroy plants are Japanese beetles. Damage can be extensive as they invade in groups, devouring roses, vegetables, and fruit trees.
Adult Japanese beetles are most active June through August . During this time, they (see picture above) are very damaging to the upper surface of foliage while the grubs attack plant roots. Therefore, it is vital that you get rid of them quickly.
Below we’ve gathered some of the bestand organic methods to do away with these destructive insects.
Here’s how to get rid of Japanese beetles naturally.
1. Pick Them Off
This method is time-consuming and tedious, but it’s the most productive home remedy. Hand-pick and throw them into a container with soap and water to suffocate and drown.
2. Neem Oil
Extracted from the seeds of the neem tree, neem oil is a common organic pesticide used by backyard farmers worldwide.
Add a small amount (2 tablespoons) to one gallon of water and spray crops every 7 days while the pests are feeding.
The solution will harm the beetles when they ingest it. It will also interfere with their eggs, preventing them from hatching.
3. Row Covers
Row covers or garden fabric blocks harmful pests from getting to the crops.
Following the installation manual, fix row covers over the crops using plastic hoops or wooden frames for support. Next, secure the edges with staples.
4. Beneficial Nematodes
These are live microscopic organisms that are natural predators for Japanese beetle grubs and/or pupae. They get into the body openings of these pests and find their way to the bloodstream, killing them within two to three days.
The nematodes can be dispersed into the soil using a watering can, and the best time to apply is in the evening as they do not like direct light.
Also, enough moisture provides a conducive environment for them to thrive. Therefore, it’s advisable to sprinkle enough water into the garden before and after the application of nematodes.
5. Diatomaceous Earth
Diatomaceous earth causes the beetles to die from dehydration by cutting through their protective outer shell, destroying their exoskeleton.
To use, sprinkle it on the leaves, stems, roots of the plants, and on the garden soil around. Besides, you can use it inside the house, sprinkled directly on the bugs when they are visible.
6. Soap and Water
Spraying your plants and lawn with soapy water is beneficial in curbing the problem. It forces Japanese beetle larvae to the soil’s surface where predators come to feast on them.
This homemade Japanese beetle spray also works on adults. Pick or shake them off into a bucket of soapy water. Consequently, it will kill them by way of suffocation.
Four to five tablespoons of organic liquid soap to a gallon of water is the recommended ratio.
7. Companion Planting
While planting crops that are susceptible to beetle attack, consider planting together with plants that keep the pests away.
Some of the plants that repel Japanese beetles are marigolds, nasturtium, chives, tansy, catnip, and rue.
8. Fowls and Birds
Poultry and birds are good predators to adults as well as the grubs.
Attract these animals to your garden or yard by providing them with food and water. Some birds eat the adult beetles while others dig up the grubs.
9. Vacuum Them
Every day, dedicate some time to vacuum the infested plants and put the vacuum’s content in a container full of soapy water to kill the critters.
10. Cedar Oil
An excellent natural Japanese beetle repellent is cedar oil. It has a long-lasting smell that keeps them away.
Combine four tablespoons into a gallon of water. When sprayed on plants, its strong scent will keep the pests off.
Geraniums immensely attract Japanese bugs. However, after feeding on the blossoms, they will get dizzy and lay on their backs.
In that state, they are left vulnerable to predators. You can also pick them off and drop them in soapy water to kill them.
12. Kaolin Clay
Kaolin clay helps keep off beetles eating leaves by creating an irritating whitish film on leaves and fruits.
Our recommended brand is Surround WP.
Mix 3 cups in a gallon of water and coat your plants. Moreover, you can use this natural spray up until the harvesting day.
13. Milky Spore
Milky Spore contains spores of the naturally occurring bacterium Paenibacillus popilliae, which destroys the grub stage of the beetle.
When dispersed into the soil, the grubs must ingest the spores when feeding. When this happens, the spores reproduce inside the pests, killing them within 7-21 days.
Pyrethrin is a natural insecticide that aims at the nervous systems of insects. However, you should avoid using it when beneficial insects and pollinators are around.
Once the insects come across it, they become paralyzed and eventually die.
15. Beauveria bassiana
Once the beetles come into contact with the fungi, they get infected. This is when you’ll notice a whitish coating on them. As a result, they’ll die within one to two weeks.
Sold at most well-established gardening centers, Japanese beetle traps produce a scent that’s inviting to the adult bugs. Once they are trapped, you can get rid of the culprits.
However, the scent may attract other critters that are not within your garden, and not all of them are likely to be captured.
17. Avoid Watering Lawn
One of the simplest Japanese beetle control home remedies is to avoid excess watering during their season. The beetle’s season runs from June through August or September.
During this period, watering the grass is discouraged as moist lawns provide a conducive environment for their eggs to survive.
18. Bacillus thuringiensis (Bt)
BT is a soil-dwelling bacterium. It produces proteins that are toxic to Japanese beetle grubs. After consuming the toxin, it poisons and paralyzes them.
19. Drop Cloth
A drop cloth is handy for this purpose, especially in the early morning hours when the beetles are very active.
Spread the cloth in the garden. Once the critters are on it, shake them off in a bucket full of soap water.
20. Garlic Spray
A mixture of garlic, liquid soap, and water sprayed directly on the affected plants is great for preventing Japanese beetles from coming around.
Puree 5 cloves of garlic into a cup of water. Next, add a teaspoon of little liquid soap to the mix, then strain and spray your plants.
Use the measurement as a guide for larger concoctions. The beetles hate the smell of the solution, so they will not come near once it’s applied.
21. Parasitic Wasps
Attracting parasitic wasps in your garden can be an effective way of controlling the larvae’s population. However, parasitic wasps are not useful when it comes to handling high numbers of pests.
The critters mainly go after plants such as roses, dahlias, petunias, zinnias, apple trees, basil, birch, berries, shrubs, and corn. Therefore, be on the lookout and take action before an infestation begins.
The natural methods listed here have no adverse effects on the environment. Besides, they are budget-friendly.