Natural Bug Repellent for Perennials

Garlic Spray

• Onions, garlic and spicy peppers are great not only for whipping up your favorite Mexican meal, but also for deterring insect invasions. Toss into a blender an onion, a bulb of garlic and a teaspoon of spicy pepper powder. Blend until the mixture has a coarse, minced texture, then add a quart of fresh water and let the solution sit for a few hours. Afterward, strain the mixture through a sieve or a square of cheesecloth to separate the herbs from the water. Pour the water into a spray bottle. If you want to not only repel bugs but also kill them, add a tablespoon of dish detergent. Spray the mixture onto any plant experiencing bug problems.

Horticultural Oils

• Commercially prepared bug sprays formulated from vegetable horticultural oils, specifically neem, cottonseed and soy oil, have powerful insect-killing, insect-repelling and fungicidal powers. They are commonly used against smaller insect pests, such as whiteflies and aphids, and work best when sprayed onto dry plants. Because newly sprouted plant tissue may react sensitively to horticultural oils, reserve their use for mature perennials.

Companion Planting

• Several specific plant species possess horticultural compounds or odors that repel pests from your garden. By interplanting such species among your perennial plants, you can create natural barriers against some pest problems. Common examples include garlic plants, which guard against aphids and various kinds of mites and beetles; marigolds, which also repel beetles; and basil, which deters hornworms.

Pyrethrum Spray

• Commercially prepared insecticides made with pyrethrum work as an organic, all-natural insecticide and deterrent spray. It's created from a certain kind of Chrysanthemum flower. Pyrethrum is commonly used against all kinds of bugs, including stink bugs.

Diatomaceous Earth

• Diatomaceous earth, a white dustlike substance created from natural rock, offers up microscopic, sharp surfaces that soft-bodied bugs can't handle. When dusted onto perennials or on the ground around them, the earth creates a physical barrier against pests such as worms, caterpillars and slugs.