Herbs That Repel Insects in Gardens

Mints

• Mint's highly aromatic foliage repels ants, reports "Mother Earth News." Michigan State University reports that mint planted around foundations of homes not only repels ants but also the aphids they carry. Flies and fleas find mint's odor repellent and avoid mint plantings. Although most herbs require full sun, mints are shade-tolerant and thrive in shady, moist garden areas. Planting mint around dog houses does not kill fleas but acts as a repellent to block unwanted pests from Fido's retreat.

Fennel

• A rhyme for remembering another living herbal flea repellent is "plant fennel outside your dog's kennel." Brigham Young University's Companion Planting Guide cautions against growing fennel near tomatoes, however, because fennel inhibits growth of tomato plants, so the herb should be sited away from your vegetable garden. Because this herb does not transplant well, you should direct-sow seeds where plants will grow.

Basil

• Basil is a culinary plant companion to tomatoes as well as an insect repellent companion. Brigham Young University recommends planting three basil plants around each tomato plant to repel tomato hornworms, caterpillar larvae that attack tomato plants vigorously. Windowsill basil gardens repel fleas indoors, according to Michigan State University. Although basil is an annual herb, it grows easily in sunny windows during winter. Potted in containers on decks or patios, basil repels flies and mosquitoes.

Garlic

• The International Herb Association voted garlic as the 2004 Herb of the Year. Culinary benefits are well documented, and pest-repellent benefits are substantiated by university researchers. Alabama Cooperative Extension recommends planting garlic at the base of fruit trees to repel Japanese beetles and planting throughout the garden to repel aphids, caterpillars, borers and mites. Brigham Young University cites garlic as a companion plant that protects apple trees from scab, peach trees from leaf curl, and tomatoes from red spider mites.