Pests are the bane of every gardener’s existence. There is nothing as heartbreaking as spending all season tending lovingly to a plant just to have them succumb to beetles or aphids.
Especially for gardeners who are trying to avoid pesticide use, repelling pests can be very challenging. Luckily, nature has developed some ways to deter pests that you can take advantage of in your own garden without using man-made chemicals. Here are some plants that keep bugs away.
Growing “trap crops” to deter pests
If you have problems with a specific pest, you can even grow a whole row of a certain plant that are just meant to attract the pests away from your other crops.
“Grow a ‘trap plant’ that will trap the pests attract the pests,” said Kate Garland, horticultural specialist at the University of Maine Cooperative Extension.
Garland said that the Bangor Community Garden in Bangor, Maine, grows giant pumpkins and blue hubbard squash near garden plots to attract cucumber beetles away from the precious crops of unsuspecting community gardeners.
“The blue hubbard squash seems to be much more appealing,” she said. “You can hand pick them and remove them much easier on the trap crop. You can still get some fruit off them, but the main value is to trap pests.”
Aphids are also susceptible to the wiles of trap crops. “There are certain plants they really do like,” Garland said, like nasturtiumand nettles. “If you plant them, you know aphids are more likely to go to that trap crop.”
Companion planting to deter pests
There are also certain pairings of plants that work well to repel pests. You can plan your garden plots with companion planting in mind to keep pests at bay.
“There are quite a number of herbs that are going to be pest repellant,” said Leonard Githinji, Assistant Professor and Extension Specialist Sustainable and Urban Agriculture at Virginia State University.
Basil, he explained, are naturally good pest repellents for tomatoes (luckily enough for caprese salad and tomato sauce enthusiasts). Dill will keep boring bugs away from squash vines. Rosemary will help protect carrots and beans from common pests as well.
There are also some vegetables Githinji suggested as companion plants to deter plants. Radishes are effective deterrents against bugs that attack squash and cucumbers. Planting tomato and corn together, he said, will also help prevent earworms.
“Leeks will produce aroma that will keep bugs away like flies that attack carrots,” he added.
Another pairing that Githinji suggested is spinach and strawberries, for a tasty, bug-free summer salad.
Plants that naturally deter pests
The research is not particularly robust when it comes to evaluating which plants universally deter pests.
“There’s a lot more anecdotal stories than there is actual scientific evidence about a lot of them,” Garland explained.
Nevertheless, there are some plants that are considered better pest repellants.
“Chrysanthemum is one example of a plant with insect repellant characteristics,” Garland said. Pyrethrin, which is derived from chrysanthemum flowers, is used in many commercial pesticides.
“In general, marigolds are a plant that can repel pests,” Githinji added.
Garland said that the only research-based evidence she has seen for marigolds is that they are effective at repelling soil nematodes, but given the other benefits of having marigolds in the garden, she suggested planting them anyway.
“The benefits of having more pollinators around and the attractiveness of the plant is a good thing,” Garland said. “Marigolds are also a good trap crop for slugs.”
With these handy tips to start, the best thing to do is to experiment and determine the plants that keep bugs away in the microbiome of your garden.
This is a guest post written by Sam Schipani. Sam is a staff writer for Hello Homestead and the Bangor Daily News. She loves watching hummingbirds, eating flowersand shopping sustainably. She has previously written for Sierra, Smithsonian, Earth Island Journal, and American Farm Publications.