Planted around the foundation of the home, mint, pennroyal and catnip will keep out ants. Used as an oil, mint will repel mosquitoes. Pennroyal used alone will also repel mosquitoes, flies, fleas and ants. Catnip is 10 times more effective than the chemical known as DEET for keeping away mosquitoes, according to Planet Green.
Lavender repels fleas, moths and mosquitoes. To repel fleas, sprinkle powdered lavender on your pet's bedding. To repel moths, hang a bunch in your closet or sprinkle sprigs in with clothes being stored. To repel mosquitoes outdoors, grow lavender in containers.
Pyrethrum is part of the chrysanthemum family. The flowers have been used for centuries as a natural insect repellent, according to the HipHerb website. Planted in the garden, pyrethrum effectively repels ants, mosquitoes and other insects. In the home, the ground dried flowers of the pyrethrum repels roaches, flies, ants, mites and other household insects The plant is toxic to insects but not mammals.
Bay leaf will repel weevils in dry food products such as white flour, barley, rice, wheat berries, cornmeal, quinoa and oatmeal. Spreading bay leaves around the pantry will repel roaches, moths, earwigs and flies.
The leaf of the tansy plant is added to sachets or can be hung indoors to repel insects such as moths, fleas, flies and ants. Planted in the garden, tansy repels aphids and other insects.
A wide range of additional herbs are also known to be especially helpful in repelling mosquitoes. Mosquito repelling herbs include rosemary, lemongrass, wormwood and basil.
As herbs continue to be used as a natural alternative to synthetic pesticides, additional but less well-known herbs are also useful. This includes alecost, chervil, caraway, curry plant, southernwood, rue, santolina, sweet woodruff and melilot.