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Controlling Japanese Beetles in Your Garden

Environmentally Friendly Options for Beetle Control

Japanese beetles are destructive copper colored beetles that decimate all plant life they come in contact with. The beetles attack everything from ornamental flowers, to fruit, to vegetable crops. Controlling Japanese beetles in your garden can become a full time task if not approached correctly.

Grubs

Start controlling Japanese beetles at the grub stage. Milky spore disease is a natural control for the grub stage; however it does not affect adult beetles. Controlling Japanese beetle grubs is important. It breaks the life cycle of the beetles and it will control the grubs that are eating your lawn.

Adults

Traps are one of the most effective ways to control adult Japanese beetles. Pheromone traps lure the male beetles to their demise, thus breaking the life cycle by removing the males from the population.

Another way to control the adult beetles is with homemade organic sprays. Boil ¼ cup of chopped jalapeño peppers and ¼ cup of cayenne pepper flakes in a covered pot. Once the water boils, reduce the heat to simmer and let it cook for an hour. Strain out the solids and pour into a hand sprayer. Wear gloves if you are sensitive to hot peppers and avoid getting the steam into your eyes. Add a teaspoon of rubbing alcohol to the sprayer. Shake well and spray onto your plants making sure to spray any beetles you see.

Predatory Insects

The praying mantis is an amazing insect. Its favorite food is adult Japanese beetles. You can purchase praying mantis egg cases at a local farmers supply or by mail order. Make sure that your garden has a source of water, and shrubs for protection. If these conditions are met, the praying mantis will gladly stay and devour the Japanese beetles for you.

Row Covers

For delicate plants, vegetables, and fruit, using row covers is a fail safe way to keep Japanese beetles off of your plants. In most areas, Japanese beetles only last for about a month during the summer. Covering your plants with row covers will allow water, light, and air to reach your plants without allowing the Japanese beetles in. Place the row covers on the plants one week prior to when your area is usually affected by the beetles.

Hand Picking

This is a very effective method of control. Take a bucket of soapy water with you and either shake the plants over the bucket or hand pick the beetles off of the plants and drop them into the bucket. They will drown in the soapy water. If you want to dump the beetle infested water into your compost pile, do not use antibacterial soap.

Using these environmentally safe controls for Japanese beetles will greatly reduce the amount of damage to your plants and lawn. While these controls will not eliminate the problem completely, pest management is about striking a balance. Expect some minor damage from year to year, but using environmentally sound pest controls will keep your garden performing its best year after year.