The first step in any pest control effort is prevention. Most cockroaches prefer warm, wet environments, and they eat decaying plant matter and garbage. The best way to keep cockroaches out of your car is to keep the interior clean and free of trash, especially food trash. If you live somewhere humid, even a few crumbs can be enough to bring in a hungry roach. Cockroaches even eat glue and paper, so all the trash has to go. It’s also probably a good idea to keep the area around where you park free of leaves and other ground-covering debris. If they don’t hang out around your car, they’re less likely to find any dropped food inside your car.
But you’re probably not here because you want to keep cockroaches from infesting your car. You’re probably here because you’ve already seen at least one cockroach in the car, you’re worried there may be more, and you want to know how to get rid of them.
Maybe you’ve found a cockroach in your car and you want to just live and let live. However, cockroaches are actually a dangerous pest. Not only can they eat pieces of your car or any clothes you may have left in there, but they carry bacteria, viruses, and allergens. They can make you sick.
Do a thorough clean
- Step one is a thorough clean. That means every bit of trash in your car, food and otherwise. Pull up the mats, take off the seat covers, and break out the vacuum. Or better yet, get your car detailed. This ensures that once you get rid of the cockroaches, they won’t come back. But that just step one. Some cockroaches, like the American cockroach, can live for up to three months without food, so you’re not going to get rid of them just by taking out the trash.
- Step two is to get rid of them. There are several ways to control a cockroach infestation, with varying levels of effectiveness and safety.
Use roach killer powders or cockroach bait
A simple extermination method is to use a powder like boric acid, borax, silica aerogel, or diatomaceous earth. Boric acid is a chemical pesticide and borax is a mineral. They enter the insect’s digestive and nervous systems and kill them. Silica aerogel and diatomaceous earth are moisture-absorbers that kill insects by dehydrating them. You can mix any of these products with little something cockroaches like to eat, like flour, spread it in a thin layer in a jar top or other shallow container, and place them in the small, dark spaces in your car (e.g., under seats and in the trunk).
Boric acid and borax are the most effective of the four options here to eliminate your cockroach in car problem. They are also more dangerous for people and animals. Boric acid can cause a rash if you get it on your skin. If accidentally eaten, it can lead to nausea, stomach pain, vomiting, and diarrhea. When inhaled, it can dry out your mouth, nose, and throat, leading to a sore throat, cough, nosebleeds, and even difficulty breathing. These effects are worse in children and pets and are especially dangerous to infants6. Borax has some of the same effects as boric acid but also causes eye irritation. A specific effect of borax is hormone disruption, leading to reduced fertility and libido. As little as 5 grams of borax can kill a child and 10 grams can kill an adult. If you choose to go with one of these options, it’s best to leave the powders overnight and remove them in the morning before using your vehicle. This will reduce the chances of anyone touching, inhaling, or ingesting these toxic substances.
Silica gel and diatomaceous earth are less effective, but also safer. Silica gel can cause minor eye and skin irritation in the short term. However, it also may be a risk factor for some cancers in the long term. Diatomaceous earth is considered non-toxic to humans and most other animals, but it can cause lung irritation after long exposure and it is especially dangerous to bees. While these products are safer, it’s probably still a good idea to only keep them in your car overnight.
An even easier option is a cockroach bait. These are sold in hardware stores or online. All you have to do is follow the label directions. Because any insecticide is poison, however, make sure to keep them out of reach of children and pets.
Why you shouldn’t use a roach bomb in your car
You may be wondering can I bomb my car for roaches? While a roach fogger, in-car roach bombs, and similar methods can be used in the car, they’re very toxic and have limited effectiveness. For starters, they’re flammable. They’re also an aerosol insecticide, which means they disperse into the air and settle on everything, coating the interior of your car in poison. If you breathe them in, it can cause illness. Besides these dangers, they don’t work well. Very little actually ends up in the little nooks and crannies where cockroaches like to hide. What’s more likely is that you’ll just drive them deeper into your car as they try to get away from the fog. If you do decide to go this route and use a roach bomb for the car, be sure to air out your car afterward by leaving all the doors open for a while. It’s probably a good idea to blast your air conditioner, too, to make sure anything that settled in the vents gets blown out before you get in.
Any of these options should take care of your problem. However, if you have a few pests left over, you can keep a spray bottle filled with dish soap and water in your car. When you see a cockroach, spray it with the spray bottle. The dish soap will cover their bodies. Since cockroaches breathe through their skin, it will suffocate them.
Prevention is key
Finally, step four comes back to prevention. Keep your car clean and free of stuff that cockroaches like. Institute a no eating in the car rule, don’t leave trash in it and don’t park it near wood or leaf piles. And your car should be roach-free for good!