Although mostly harmless, spiders can be a nuisance in the home. Many people find these eight-legged creatures creepy. Some can even be poisonous.
If you’re someone who shrieks when you see spiders, you may want to try peppermint oil to get rid of them. Peppermint oil is considered to be a natural insecticide. Spiders, although not technically insects, seem to hate it.
There’s not much scientific research proving that peppermint oil repels or kills spiders. Most commercial pest-control companies dispute claims that essential oils work as natural insecticides. Still, there’s plenty of anecdotal evidence for peppermint oil getting rid of arachnids.
It’s unclear why spiders steer clear of peppermint oil and other essential oils. One theory is that they dislike strong odors. Because spiders smell and taste with their legs, they may avoid crawling through fragrant oils. Another theory has to do with the monoterpenoids found in essential oils. Almost all essential oils contain them to some degree. According to a 2010 study, monoterpernoids are fumigants. This may play a role in their insecticidal properties.
Another 2010 thesis found that peppermint oil repels Argentine ants for up to seven days after application. The study concluded that essential oils are viable alternatives to traditional chemical repellents because they can repel Argentine ants and other home invaders, such as spiders.
To make a spider-repellent spray, place about five drops of peppermint oil in a 16-ounce spray bottle. Fill the bottle with water, add a shot of dish soap, and shake the mixture well. Apply the spray around doors and windows, around the outside perimeter of your home, and in any dark corner where spiders may be hiding.
You’ll have to apply spider-repellent spray more often than conventional insecticides. Try applying once a week at first. If the spiders reappear before the week is up, try spraying every few days.
Placing peppermint plants in strategic places inside and outside your home may also help repel spiders. You can also try sprinkling peppermint leaves in places overrun by spiders.
Peppermint oil is generally considered safe in small doses. It does contain menthol, which may cause skin irritation. According to the National Association for Holistic Aromatherapy, inhaling large doses of peppermint oil may cause:
- muscle weakness
- double vision
Your risk of side effects increases if you spray large amounts of undiluted peppermint oil in an enclosed area. Always dilute peppermint oil and use caution when spraying it inside your home. Avoid spraying your whole house at once. Spray small areas at a time, and keep your windows open for fresh air. Spraying peppermint oil around the outside perimeter of your home is less likely to cause side effects.
According to the ASPCA, mint is toxic to dogs and cats. They don’t have to eat it to get sick. Even inhaling mint may cause severe symptoms. If you have dogs or cats, avoid using peppermint oil in your home unless it’s in an area your pets can’t access.
Though there’s little scientific research on the effectiveness of essential oils to repel spiders, there are several oils you can try. These include:
- lemon oil
- eucalyptus oil
- lavender oil
- tea tree oil
- citronella oil
Spreading cedar mulch around your home may help deter spiders and other bugs from moving in. A cedar sachet in your closet and drawers may also discourage them.
Sticky glue traps normally used to catch flies may also catch spiders. Place them around your baseboards and in other places where you’ve spotted spiders.
Most stores carry insecticides that claim to kill spiders. If you’re uncomfortable using insecticides, you may want to hire a professional pest control company to do the job. Some common ingredients used to kill spiders and other bugs are:
Carbaryl is the common name for the pesticide chemical l-naphthyl methylcarbamate. It kills spiders and other bugs by disrupting their nervous system. It’s available in dust, liquid, granule, wettable powder, and trap forms.
Pyrethrins and pyrethroids
Pyrethrins are natural insecticides made from chrysanthemum flower extract. Pyrethrins have been used as prototypes to create man-made chemical insecticides called pyrethroids, which are longer lasting. Both pyrethrins and pyrethroids stimulate the nervous system of spiders, which leads to paralysis and death. They’re available as foggers, bug bombs, dusts, and liquids.
No matter how successful you are at battling spiders, they’ll probably be back unless you do some clean-up work. The best way to keep spiders at bay over the long term is to make your home less attractive to them by:
- dusting and vacuuming regularly, especially around baseboards, windowsills, and in corners
- removing visible cobwebs and spider egg sacks
- removing leaf piles, compost piles, and debris piles near your home
- storing firewood as far away from your home as possible
- making sure window screens and doors are well-sealed
- caulking any cracks in your home’s foundation
If you decide to try peppermint oil to repel spiders, be patient. It may take time to get control of the problem. Severe spider infestations or infestations by dangerous, venomous spiders may require the help of a professional exterminator.