What Flowers Keep Pests Away? | 12 Plants That Actually Work

Marigolds, chrysanthemums, lavender, and several other common flowers naturally deter garden pests through their scents and compounds, but they work best as one part of a broader pest-management plan, not as a standalone fix.

For the full breakdown, see our best Pest Control For Flowers guide.

Every gardener has been there—you spend weeks tending tomato starts, only to find hornworms munching through them overnight. The good news is that certain flowers pull double duty in the garden: they look good and make life harder for the insects you don’t want. None of these plants will eliminate pests entirely on their own, but planted strategically, they reduce damage noticeably.

Which Flowers Repel Garden Pests Best?

The most reliable pest-repelling flowers target specific insects through their natural compounds. Here is how the top performers line up against common garden nuisances.

Marigolds are the most versatile option. Their roots release thiopenes that deter nematodes underground, while the flowers above ground repel aphids, whiteflies, tomato hornworms, cucumber beetles, and mosquitoes. Plant them around vegetable beds as a living barrier.

Chrysanthemums contain pyrethrins, a natural insecticide compound that targets ants, roaches, ticks, fleas, spider mites, and Japanese beetles. The compound is potent enough that many commercial organic sprays use it as their active ingredient.

Lavender works well against mosquitoes, moths, flies, fleas, and ticks. Its strong scent masks the odors that attract these pests, and it keeps working even after the flowers are dried and hung nearby.

Other strong choices include petunias (against aphids, tomato hornworms, and squash bugs), nasturtiums (against bean beetles and whiteflies), and geraniums (against leafhoppers, mosquitoes, and Japanese beetles).

How Should You Plant These Flowers for Pest Control?

Companion planting—placing these flowers around and between vegetable rows—is the method that sources consistently recommend. Simply dropping one marigold in a corner will not do much; the effect comes from density and variety.

Here is the practical approach:

• Plant a border of pest-repelling flowers around the entire garden perimeter.
• Intersperse them between rows of susceptible crops, not just at the edges.
• Use at least three different flower types so one pest’s weakness is always covered.
• Keep plants healthy with regular water and deadheading—stressed plants produce fewer repellent compounds.
• Refresh plantings every growing season; annuals like marigolds and petunias lose effectiveness as they fade.

One important exception: mint, catnip, and lemongrass also deter pests effectively, but they spread aggressively. Always plant mint in containers or buried pots to keep it from overtaking your vegetable beds.

What Are The Limits And Risks Of Using Flowers As Pest Control?

These flowers are deterrents, not eliminators. If you already have a severe pest infestation, repelling plants alone will not stop it. They work best as a preventive measure for healthy gardens with manageable pest pressure.

Several important cautions apply. First, some plants labeled “natural” can still cause skin irritation on contact, and certain species—particularly chrysanthemums in high concentrations—are toxic to pets if ingested. Research each plant before adding it near areas where children or animals play.

Second, pest control claims vary across sources. Marigolds (Tagetes spp.) are often confused with pot marigold (Calendula officinalis), which is less effective against pests. Stick with the true Tagetes marigolds for best results.

Finally, sunflowers act as a trap crop that actually attracts aphids rather than repelling them. Do not count them among your deterrent plants unless you intend to use them as sacrificial decoys away from your main crops.

Best Flowers At A Glance

No single flower solves every pest problem, and these plants will never make insecticides obsolete. But when you combine several species, plant them densely, and keep them vigorous, they reduce the number of pests that ever reach your vegetables—and they make your garden look great while doing it.