Lemon Balm
Lemon Balm contains high levels of a compound called citronellal, which gives it its lemony aroma and flavor that bugs find so unpleasant. Crush the fresh leaves and rub them directly on the skin, especially around ankles, arms, and other areas most exposed and vulnerable to bug bites. The lemon scent, which repels the bugs, is powerful. It rubs off very well onto the skin. Lemon balm repels mosquitoes and gnats.
Marigolds
Commonly grown as ornamental border plants, marigolds are hardy annual plants which have a distinctive smell which mosquitoes, and some other insects, find particularly offensive. Marigolds contain Pyrethrum, a compound used in many insect repellents.
Mint
Mint deters white cabbage moths, ants, rodents, flea beetles, fleas, and aphids. It improves the health of cabbage and tomatoes. Mint flowers attract hoverflies and predatory wasps. Earthworms are quite attracted to mint plantings. Be careful where you plant it as mint is an incredibly invasive perennial. Placing peppermint cuttings (fresh or dried) where mice are a problem is very useful in driving them off! Mint and parsley are enemies. Keep them well away from one another.
Pennyroyal
Excellent insect repellent for ants, fleas, and ticks. The leaves, when crushed and rubbed onto the skin, will repel chiggers, flies, gnats, mosquitoes, and ticks.Warning: Pennyroyal is highly toxic to cats. It should not be planted where cats might ingest it and should never be rubbed onto their skin.
Peppermint
Biting bugs don’t like the scent of peppermint, so you can crush up the leaves and rub it on your skin to ward them off. As a bonus, peppermint also can do double-duty as itch relief if you do get bitten!
Rue
Rue deters aphids, fish moths, flea beetle, onion maggot, slugs, snails, flies, and Japanese beetles in roses and raspberries. Companions for rue are roses, fruits (in particular figs), raspberries and lavender. To make it even more useful with Japanese beetles: crush a few leaves to release the smell. Also, it has been known to repel cats. You should not plant rue near cucumbers, cabbage, basil, or sage. A pretty perennial with bluish-gray leaves, rue may cause skin irritation in some individuals.
Sage
Sage repels the same insects as rosemary, especially snails, cabbage moths, beetles, black flea beetles, and carrot flies, as well as flea beetles, which prey on potatoes and sweet potatoes. Do not plant near cucumbers, onions, or rue.
Tansy
Plant with fruit trees, roses, and raspberries, keeping in mind that it can be invasive and is not the most attractive of plants. Place Tansy clippings by the door as an ant repellant. Deters flying insects, Japanese beetles, striped cucumber beetles, squash bugs, ants, and mice! Tie up and hang a bunch of tansy leaves indoors as a fly repellent.Tansy Warning: You do not want to plant tansy anywhere that livestock can feed on it as it is toxic to many animals. Do not let it go to seed either as it may germinate in livestock fields.
Thyme
Deters insect pests and also helps with preventing musty odors; use in sachets, both flowers, and leaves.
