14 Plants Which Repel Insect Pests
The flowers make a relaxing tea, and also emit chemicals, pyrethrins, which act as an effective insect repellant. This actually affects all insects, and when concentrated, it can even inhibit female mosquitos from biting. Unfortunately, “all insects” includes pollinators, so don’t expect many fruit or seeds nearby.
They also repel non-garden insect pests, inluding ticks, lice, fleas, and silverfish. Grown as houseplants, chrysanthemums can also help clean the air.
A lot of old school gardeners will tell you to plant Marigolds everywhere in your garden, because they can act as companions to all kinds of plants. They both attract beneficial insects like pollinators, and repel unwanted insects – including root-knot nematodes, beet leaf hoppers, cucumber beetle, squash bug, onion fly, and cabbage root fly.
French marigolds emit a pesticidal chemical from their roots, which is strong enough to stay in the soil for some time after the plant is gone. Mexican marigolds do the same, but are powerful enough to even affect some more delicate plants, so they should be used sparingly!
Onions not only taste great, but they’re excellent at repelling pests. Among others, they keep away aphids, Japanese beetles, potato beetles, carrot flies, and even rabbits.
Garlic is even more effective, repelling aphids, slugs and snails, tree borers, cabbage maggots, and ants.
Growing peppermint or spearmint (and probably other types of mint too) will keep away aphids, onion fly, cabbage root fly, and ants. Be careful though, as mint grows prolifically and will happily take over your garden. Keep it in a pot. If you have pets, spearmint also repels fleas. Cats are quite fond of it too.
I love fresh chives. Several insects do not, including mites, aphids, cabbage worms, carrot fly, and nematodes.
A certain percentage of people have a genetic trait which makes the taste of corriander leaves unpleasant and overpowering to them. But even if you’re one of those people, it’s a helpful plant to grow, because it keeps away aphids, whitefly, and potato beetle. It’s also one of the few plants that can repel spider mites.
I mentioned above that onions repel carrot fly. Conveniently enough, carrots repel onion fly.
An extremely useful herb to plant around leafy greens, fennel repels aphids as well as slugs and snails.
These plants are very good at defending themselves. They’ll repel some pests, but they’re also good at attracting predatory wasps which will take care of insects pests. Mustard plants also have a more extreme method of self defence – if anything lays eggs on the plant, it’ll sacrifice part of the leaf those eggs are laid on, so the eggs fall off.
These are very pretty flowers, which can keep a load of insects at bay. In particular, they repel aphids, whitefly, squash bug, carrot fly, and numerous types of beetle. They also repel most major cabbage pests.
A mild flavoured herb, which can repel spider mites, as well as aphids, squash bugs, and cabbage looper.
A tasty salad herb which goes nicely with sundried tomatoes, and repels a few different insects, including mosquitos. Unfortunately, aphids love it, so you should choose a good companion plant for it.
You can brew a nice relaxing tea from catnip. It can also repel aphids, squash bugs, weevils, and various beetles including cockroaches. Of course, it’ll also attract cats. Which may or may not be a bad thing, depending on whether you like cats.
Tastes good in cooking, smells good as incense, and keeps away cabbage fies, carrot fly, black flea beetle, cabbage looper, and cabbage maggot. Grow it near beans to protect them from various parasites.