Lavender, savory, wormwood, rue and pennyroyal are all effective against fleas. Try placing dried branches and leaves under the pillow in your pet's bed. Place bouquets of herbs, either fresh or dried, on windowsills. Repellents last longer when rubbed on clothing rather than skin. Don't apply the oil from a crushed herb or an oil extract on skin until you're sure it is safe.
Many people are allergic to herb oils.
Tansy grown near a doorway discourages flies and ants. Fleabane burned as a fumigant will drive away mosquitoes as well as fleas. Rue, tansy and pennyroyal chase away ants. Should an insect happen to slip through your net of precautions and you receive a bite, there is a ready solution in the herb garden. An infusion made from hyssop stems and leaves will also bring blessed relief.