Chestnuts are often touted as among the most effective organic spider repellents. The oil contained within these nuts is thought to produce an odor that spiders detest. To use chestnuts to deter spiders, sprinkle fresh nuts around doorways, window sills and baseboards, concentrating on areas in which you have seen spiders in the past. Replace the chestnuts every seven to 10 days to ensure freshness.
Many insects, as well as spiders, are repelled by the essential oils present in citrus fruits along with the accompanying strong odor. Using citrus fruits to repel spiders in the home can be as simple as applying a lemon-scented cleaning solution on your counters and by adding a few drops of lemon oil to your mop water. You can also concoct your own homemade spider repellent spray by adding 10 to 20 drops of lemon oil to a pint of water in a spray bottle. Spray it directly on plants and surfaces in your home.
Essential oils of all kinds are known to repel spiders. One oil commonly used in homemade bug sprays is citronella oil, derived from citronella grass. This grass has a strong, aromatic odor, which makes it effective as a natural spider repellent. Use citronella grass in or bordering your garden, or as a companion plant to ward off spiders and insect pests. You might try growing citronella grass in small pots in the kitchen to keep spiders away from food, surfaces and cabinets.
Commercial insecticide sprays are generally ineffective against indoor pests like spiders, and many are unsafe for use in homes where children and pets are present. Many commercial pesticides and insecticides contain toxic chemicals like diazinon and atrazine, which can cause headaches, vomiting and serious neurological problems. Using natural substances like plants is a safe and effective way to rid your home of pests without putting your family at risk.