Prevent Next Years Grubs in June & July

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Japanese beetles are out and whether you have a few, or millions, now is a good time to start thinking about control for next year. As soon as they appear, the adult Japanese beetle starts looking for a place to lay eggs for next year’s crop of beetles. They hover over the lawn and lay their eggs just under the surface of the soil. Eggs hatch around mid-August.

During this time period when the eggs are in the soil before hatching, an insecticide containing imidacloprid can be applied. This product is very effective and prevents eggs from hatching into young grubs. But, you have to be sure and apply the insecticide after eggs are laid but before the eggs hatch. Products such as Merit and Bayer Advanced Season Long Grub Control are readily available to consumers and come in both granular and liquid formulations. Just be sure that the product you purchase contains imidacloprid.

There should be a noticeable reduction in the numbers of Japanese beetles in the garden next summer. Just remember that insects don’t respect property lines and the neighbors’ beetles can come over to visit.

There is another time period when Japanese beetle control is effective. A different insecticide is used and it is applied at a different time of year. Be on the lookout for another Japanese beetle article in the coming fall.

Products for controlling those beetles that are eating in your garden now are carbaryl (Sevin), malathion and permethrin. Don’t forget our pollinators when using these products. Apply late in the evening when pollinator foraging is done for the day. Remember that Japanese beetles are active during the day and that they must ingest the chemical. Repeat applications are necessary, especially after rainfall. If using a trap, read the directions before choosing the site for the trap. This is crucial.