How to fight pests with plants
Before there were powders, dusts, and sprays, plants needed their own defenses against insects and other creatures. Some developed noxious odors, while others used poisons and unpleasant flavors to protect themselves. Ancient farmers picked up on these characteristics, discovering that “pesticide plants” grown alongside cultivars resulted in better yields and less labor-intensive growing. Companion planting was born. No matter how you spin it, toxins are bad for your health. Using them in your yard could affect you, your family, and your loved ones. But garden pests certainly aren’t going to disappear on their own. What to do? You can find examples of pesticide plants stretching back thousands of years. Native Americans, for example, may have developed companion planting as early as 10,000 years ago, long before home gardening became a pastime. Although synthetic chemical-based pesticides have become common, you don’t need to follow that trend. When you use plants to keep pests away, you’re employing a proven gardening technique backed by scientific research. Installing the right plants in your garden is fast, easy, and (the best part) extremely fun. If you’re not sure where to start, we have some suggestions for every planting zone in the US.
What to plant in the west
Western America is known for hot, dry summers with little rainfall. This means that your pesticide plants should be particularly hearty and drought-resistant. Sunflowers (Helianthus) are a trap species for destructive pests like beetles, a great way to feed birds with nutrient-rich seeds, and an excellent method of attracting predators for pest control. Sunflowers “trap” insects by keeping their attention away from the rest of your yard, giving sensitive plants a chance to thrive. Rosemary (Salvia rosmarinus) repels soft-bodied pests such as snails and slugs. Lavender (Lavandula) can deter both insects and mammals, including deer. Borage (Borago officinalis) is a hardy and disease-resistant plant that repels vegetable pests like cabbage worms. Sometimes called the “starflower,” this herb attracts many types of pollinator species, and has fuzzy, edible flowers in the summer. Common chrysanthemums (Chrysanthemum × morifolium) are an ingredient in many natural pest control mixtures, releasing powerful chemicals known as pyrethrins.These flowering plants are best grown near entry points like doors and windows, where they can deter fleas, ticks, and sometimes bed bugs. Nasturtiums (Tropaeolum) are considered to be one of the strongest pesticide plants available. They repel small insects such as squash borers and whiteflies, while attracting predatory insects like wasps.
What to plant in the north
Cooler areas of the US can be tricky growing spaces. Finding adequate pest-deterring plants is no exception. Be sure to hone in on plants that suit your gardening skills well. Garlic (Allium sativum) works well against rodents, including mice, gophers, moles, and voles. Catnip (Nepeta cataria) deters mosquitoes and fruit flies. Some scientists theorize it could be just as effective as DEET (without the harmful effects to people or pets). Marigolds (Calendula officinalis) are useful against some types of plant-destroying worms called nematodes.
What to plant in the south
High humidity and tropical storms means southern growers should rely on blight-resistant plants. Humidity allows fungus and mold to spread rapidly, while frequent rainfall allows mold to infest new soil. Planting options usually include hearty perennial varieties that can be purchased at any plant store. Daffodils (Narcissus poeticus) are a spring-blooming bulb plant with the ability to deter moles. Their ability to return year after year makes them an easy pick. Petunias (Petunia × hybrida) eliminate pests that destroy vegetable gardens, including tomato hornworms, aphids, squash bugs. Your end goal is a toxin-free yard. Once you’ve succeeded in keeping synthetic pesticides out of your yard, you’ll be able to reap the benefits of increased biodiversity around your home, a stronger garden, and a physically healthier crop yield. You’ll fall in love with all your new, helpful plants in no time.
