Larkspur is mildly toxic to people and pets, but it will keep Japanese beetles away. Their purple, blue, pink, and white cone-shaped blooms will also add color to your garden.
Tansy is a perennial herb that can also deter Japanese beetles because of its intense floral aroma. Tansy grows well with raspberries, which are a favorite of pests.
Growing garlic and chives, which is often grown as an annual crop but can also be grown as a perennial, will deter Japanese beetles because they don't care for either scent.