Which Plants Can Repel Bugs?

Medically Reviewed by Dany Paul Baby, MD on November 11, 2022
5 min read

Bugs are everywhere. They're an unavoidable part of life and a nuisance we all have to endure. As such, over the years we've developed plenty of ways to repel pests from our homes and bodies.

While there are many brands of bug repellent on the market, some people prefer to choose something natural or plant-based to keep bugs at bay.

Bug sprays and other types of bug repellent items can be irritating and smelly to humans. To replace them, many people turn to natural insect repellents like plants. There’s a wide variety of plants that repel bugs and insects.

Ants. There are more than 12,000 species of ants (Formicidae family) around the world. While ants only bite if threatened, they can carry mold, yeast, and many species of bacteria that can cause food poisoning and other illnesses. 

One study published in Florida Entomologist in 2014 found that of seven types of essential oils, oil made from chili pepper was most effective at repelling fire ants, followed closely by cedar. Several other plant oils used in the study were found to be effective for repelling ants, including those made from pine, mint, and clary. Another study published in the International Journal of Biotechnology and Biochemistry in 2017 found that essential oils made from clove and peppermint were especially effective at repelling carpenter ants. 

House flies. House flies (Musca domestica) are an obnoxious species of fly found all over the world. While house flies don’t bite, it’s suspected that they may spread up to 65 different diseases, including:

  • Anthrax: Anthrax is a bacteria that causes severe illness and, if untreated, death.
  • Cholera: Cholera is a diarrheal infection caused by ingesting bacteria.
  • Dysentery: Dysentery is a gastrointestinal infection caused by bacteria or parasites.
  • Leprosy: Leprosy is an ancient bacterial disease that can affect your skin, nerves, mucus membranes, and eyes. 
  • Tuberculosis: Tuberculosis is caused by a bacteria and usually infects the lungs, though it can affect any part of the body.
  • Tularemia: Tularemia is a bacterial disease that causes a wide range of symptoms.
  • Typhoid fever: Typhoid fever is a life-threatening disease caused by bacteria.

Plants that repel house flies include:

  • Blue gum (Eucalyptus globulus): Blue gum is a species of eucalyptus that repels and kills flies.
  • Catnip (Nepeta cataria): Catnip is a weedy herb. It’s known for making cats go wild, but research shows it also repels house flies.
  • Lemongrass (Cymbopogon citratus): Lemongrass is the plant that citronella, a common ingredient in traditional insect repellents, is made from, so it’s no surprise that lemongrass repels flies and other insects.
  • Peppermint (Mentha piperita): Peppermint can not only repel house flies but also kill house fly larvae.

Mosquitos. Mosquitos (Culicidae family) aren’t just a nuisance — they’re one of the most prolific killers on earth. Mosquitoes can carry bacteria and viruses that cause severe illnesses, such as:

  • Chikungunya: Chikungunya is a viral disease that causes symptoms like fever and pain, and can lead to chronic illness.
  • Dengue: Dengue fever is caused by a virus and can cause mild to severe flu-like symptoms.
  • Eastern equine encephalitis: Eastern equine encephalitis is a viral disease with a 30% mortality rate.
  • Malaria: Malaria is a disease caused by Plasmodium parasites. The severity of the disease depends on which Plasmodium parasite you have. Plasmodium falciparum can cause death within 24 hours.
  • West Nile virus: West Nile virus is the most common mosquito-borne disease in the continental U.S. It can lead to fever and in severe cases, death.
  • Zika virus: While most symptoms of Zika virus are mild, infection during pregnancy can lead to severe birth defects. 

A review published in Malaria Journal in 2019 gathered the results of 62 different studies on plant extract and oils, and how successful these substances were in repelling mosquitos. It found that dozens of plants had the potential to repel mosquitos. 

The plant oils and extracts with the highest rates of success, with the ability to repel mosquitos for nine to eleven and a half hours, were:

  • Licorice root (specifically Ligusticum sinense) extract
  • Citronella oil
  • Pine oil
  • Rosewood (specifically Dalbergia sissoo) oil
  • Peppermint oil
  • Mangrove (specifically Rhizophora mucronata) oil

They also found that essential oils from the following plants provided up to eight hours of protection:

  • Cajeput
  • Camphor
  • Carotin
  • Catnip
  • Cedarwood
  • Chamomile
  • Cinnamon
  • Eucalyptus
  • Galbanum
  • Geranium
  • Jasmine
  • Juniper
  • Lavender
  • Litsea
  • Niaouli
  • Olive
  • Rosemary
  • Sandalwood
  • Soya bean
  • Tagetes
  • Turmeric
  • Violet

These findings indicate that there’s hope for the development of new plant bug repellents, but more research needs to be done.

Ticks. Like mosquitos, ticks can carry several awful diseases, including: 

  • Anaplasmosis: Anaplasmosis is a bacterial infection that can cause symptoms such as fever, chills, headache, and muscle aches.
  • Babesiosis: Babesiosis is caused by the Babesia parasite and may lead to flu-like symptoms.
  • Lyme disease: Lyme disease is the most common-tick borne disease. It’s a bacterial disease that can cause fever, fatigue, headache, and a rash.
  • Rocky Mountain spotted fever: Rocky Mountain spotted fever is a bacterial infection that can lead to fever, headache, and a rash.
  • Tularemia

There are many types of natural bug repellents on the market, but not all of them work. The problem with plant-based bug repellents isn’t necessarily the ingredients; it’s that the oils they contain tend to evaporate quickly. It’s also important to note that some essential oils shouldn’t be placed directly on your skin without being diluted first. Diluting the oils can lead to less effective protection, or protection that lasts a shorter amount of time. When shopping for natural insect repellents, check the ratings and reviews to see how well they work before you buy.

You also can find recipes online for natural insect repellents. When trying to choose a recipe, consider what insects you’re trying to repel and what you need the repellent for. A recipe for a repellent that will keep ants out of your kitchen will look pretty different from a repellent used to protect your skin from mosquitos. If you’re trying to protect yourself from multiple types of bugs and insects, you need to choose ingredients that will work for all of them.

When it comes to your health, a plant-based bug repellent isn’t the best option for everyone. If you live in an area with a high rate of insect-borne diseases, choosing ingredients that are not plant-based but are still safe and proven to work, like Deet, may be the best way to stay healthy.