Gardeners can rid their plants of Japanese beetles by picking them off by hand or by purchasing a pesticide containing potassium bicarbonate. Using a parasitic nematode and spraying the garden with a mixture of dish washing soap diluted in water has shown successful results as well.
Japanese beetles live throughout the United States, but are more prevalent in the Eastern and Midwestern parts of the country. They eat almost every kind of plant and are a nuisance for anyone trying to grow plants in a garden. As adults, Japanese beetles are a metallic-blue green color with tan wings and white hairs on each side of the abdomen. Gardeners can look for the tell-tale signs that Japanese beetles are eating their plants by looking at the leaves. If only the veins remain, the culprit is this species of beetle.
By planting vegetables Japanese beetles don't like, gardeners can ensure they do not remain in the area. These beetles generally avoid things like potatoes, peas, carrots, cauliflower and geraniums.
If Japanese beetles are present, spray plants with a mixture of 2 tablespoons liquid dish detergent with 1 gallon of water. This will drive the grubs to the surface of the plants, making them easy for the birds to eat. Spray the plants weekly until no more grubs come to the top.
The most effective way of ridding a garden of beetles is to pick them off by hand..