Manage Pests Naturally With Companion Planting

By Linda Ly

Pests are a natural part of any garden, no matter how well you stay on top of pruning and fertilizing. Even watering habits can lead to more pests. Water too much and you could invite slugs and other moisture-loving pests into the garden; water too little and aphids could move in and attack those weakened and drought-stricken plants. Even the most vigorous plants can periodically be plagued, through no fault of your own. Fortunately, there are natural ways of managing infestations without ever picking up a bottle of pesticide.

Companion planting—the theory that certain plants benefit each other when grown in close proximity—can work for controlling and reducing the amount of pests that invade your garden beds. For some garden inspiration, consider these five favorite companion plants for your vegetable crops—which happen to be edible themselves!

1. Nasturtiums

Typically considered an ornamental plant, nasturtium is actually a leafy vegetable whose leaves, flowers and fresh green seeds are all edible. But nasturtium is popular in the garden for another reason: It makes an excellent trap crop. Plant it in and around your beds to lure aphids away from susceptible crops.

Be sure to rinse the leaves and flowers thoroughly with the Soft Wash setting of your Gilmour Watering Nozzle if you decide to eat your nasturtiums, as aphids and other pests may be taking up residence in them. While nasturtium seedlings need regular watering to establish themselves, they are fairly drought-resistant once the plants reach maturity.



2. Alliums

The pungent smell of the allium family (whose members include garlic, chives, shallots and onions) works well for deterring aphids, slugs, flea beetles, cabbage loopers and imported cabbage worms. Interplant them with susceptible crops like cabbage, kale, kohlrabi, tomatillos and roses. Got a few cloves of garlic laying around? Stick them in the soil among your plants, about two inches deep, and watch them sprout new leaves in a few weeks! Alliums need moderate watering throughout the growing season, so they’re ideal for growing alongside other vegetable crops.

3. Borage

This cucumber-flavored herb with clusters of star-shaped, nectar-rich flowers, is beloved by bees and other pollinators in the garden. (And for good reason—throw a few blossoms into a salad and have a taste for yourself.) It’s also beneficial in another important way: Borage repels tomato hornworms, so grow it near your tomato plants to thwart the destructive pests.

Borage is a favorite in drought-tolerant gardens, requiring little care once established. Be careful not to overwater, but keep the soil around borage moist. Keep in mind that the plant does reseed easily and freely, so be sure to pull it up before the seeds drop.



4. Basil

Basil and tomatoes are always a winning combination in food, from pasta sauce to Caprese salad. But did you know they’re also compatible in the garden? Basil repels tomato hornworms as well as aphids, flies, mosquitoes and spider mites, so it’s worth growing in your garden beds as well as near your doors and windows. Like tomatoes, basil benefits from a deep, thorough watering. Be consistent with your watering sessions by using a Gilmour water timer to soak your basil at least once a week.

Basil grown in containers, on the other hand, will need more frequent watering since the soil tends to dry out quicker in containers during summer heat spells. But basil is also useful in spring if your climate is warm enough to grow it: It makes a good companion plant for asparagus (one of the first crops to emerge in spring), as it helps control asparagus beetles.



5. Rosemary

This Mediterranean herb makes a beautiful, fragrant and drought-tolerant landscaping plant. Among its many benefits: The tiny flowers provide food for pollinators, and the scent boosts your memory and even improves your mood! The plant itself also repels carrot flies and cabbage moths, so grow it near carrots, cabbage and beans.

Rosemary is perennial in climate zones 7 and above, so be sure to give it a good, permanent spot in the garden with plenty of sun.

While companion planting might feel daunting if you’re trying to figure out which plants like each other and what they will or won’t attract or repel, remember that it’s more an art than a science. The goal of companion planting is introducing a variety of plant life to your garden, so it can achieve a natural balance in the ecosystem that negates the need for artificial pest control.