Termites are insects that can damage your home. These destructive insects bore into wood, causing it to weaken and rot. PestWorld.org reports that termites cause an estimated $5 billion in property damage each year in the United States. Keep termites away by keeping all wood away from your house, especially old wood that contacts the soil. Some plants can also help prevent termites.
This grass is native to India and has been used for perfumes because of its pleasant scent. It repels termites and is toxic to them. Vetiver grass is used to help control erosion because of its deep root system, and it is the roots that cause termites, cockroaches, ants, ticks, weevils and other insects to stay far away from the area in which it grows. BeyondPesticides.com reports that the chemical nootkatone is responsible for deterring the Formosan subterranean termite. Vetiver grass has also been used in houses to repel moths.
Hot Chili Peppers
Hot chili pepper plants can deter termites, ants and cutworms, according to The Organic Farmer in Kenya, Africa. You can also make a spray from chilies by soaking 2 cups of very hot chilies in 1 qt. of water for one day; shake the mixture, strain it and add 1 gallon of water and 1tbsp. of dishwashing soap. Spray the wood where you suspect termites exist and repeat your application every other day until you see no further evidence of termite damage.
Since 2003 the United States Department of Agriculture has tested essential oil of catnip for termite control, according to ScienceDaily.com. It has been shown to kill termites when they come into direct contact with this substance, but it is short-lived in the environment. It is unknown if growing catnip plants around the borders of your home can also deter or kill termites, but it is worth a try. The tests conducted with catnip oil are considered preliminary---its safety and effectiveness have not been officially tested.
Garlic, Mint, Marigolds
The U.S. Environmental Protection Agency advises homeowners to limit their use of pesticides for termites and all other insect pests. In their publication, "Pesticide Reduction," they suggest using common plants that are known to repel insects. Included in their list are mint, garlic and marigolds, which you can plant near your house. Mint is a perennial plant that grows well and spreads nicely in damp, partly-shady areas. Garlic and marigolds are annuals that you can plant every spring.