By Sam Wasson
Updated Nov 14, 2022
Cockroaches have been around since the cretaceous period, are immune to radiation, and can survive for several weeks without their heads. It should be clear that these disease-carrying insects are some of the most resilient and enduring pests you can encounter. With all that being said, can simple household products like borax, fabric softener, and bay leaves really get rid of them? In this article, we’ll look at homemade cockroach sprays and some of the most common DIY insecticides and see which ones can solve cockroach problems.
The most common do-it-yourself (DIY) cockroach spray is a mixture of three parts fabric softener and two parts water. While it might come as a surprise, this mixture will kill cockroaches. Like many insects, roaches breathe through tubes called tracheae, which bring in air through small holes in their carapace called spiracles. When combined with water, fabric softener can clog the spiracles, suffocating cockroaches in their tracks. However, the common myth that cockroaches hate the smell of fabric softener is untrue, and this spray will not prevent cockroaches.
Next in line for popular DIY cockroach killer is a borax-based mixture. Borax is one of the oldest at-home solutions to roaches and has stood the test of time. When consumed by roaches or exposed to their exoskeletons, borax dehydrates them. So, all you have to do is apply the borax (as a powder) along baseboards or in other locations cockroaches are seen. More popularly, borax is mixed in with bait, typically honey or sugar water, and laid out as a trap. When consumed, the borax will eat away inside the roach while dehydrating it, giving it a lethal one-two punch.
Besides borax and fabric softener, dozens of other popular DIY solutions are touted to terminate roaches. Here is a quick list of the most common would-be insecticides and a rundown of their effectiveness.
Rumor has it that crushed bay leaves act as an effective insecticide, killing roaches and keeping them out of the kitchen. This myth is a half-truth, as it does not kill roaches but will deter them. The scent of crushed bay leaves will effectively keep roaches away. However, it will only repel them from the areas you sprinkle it, which may drive the roaches to other parts of the home. Furthermore, as the scent of the bay leaf powder dissipates, it will become a less effective repellent.
Cayenne pepper is a well-known general insecticide and pest repellent. While cayenne will keep larger mammals, like rodents or raccoons, away, we suspect it’s less effective on pests like roaches. Some online articles recommend combining garlic, cayenne, soap, and water in a spray bottle to repel roaches. This mixture does kill roaches and repels them to a minor degree. But we find it likely that the effectiveness of this spray comes from the dish soap and garlic instead of the cayenne. Dish soap can suffocate roaches just like fabric softeners, and garlic has a strong scent like bay leaves, making it a decently effective deterrent. In combination, these ingredients make an effective spray, but when used alone, cayenne is not effective.
Baking soda, like borax, is lethally toxic to roaches. Unlike borax, roaches must consume it to be effective. Baking soda tastes and smells unpleasant to roaches, making it less likely for them to ingest it. Furthermore, baking soda will only harm roaches in its pure, powdered form, so any food or baked good containing baking soda is perfectly safe for them. Your best bet is to combine baking soda with another granulated attractant, like sugar. Mix equal parts baking soda and sugar in a small dish and apply it to kitchen cabinets, baseboards, crevices, water sources, and other places roaches like to hide. Check these bait stations once or twice weekly to see how many roaches they eradicate.
One of the more perplexing myths we’ve come across is that cockroaches hate cucumbers. As the online legend goes, placing cucumber slices along roach infest areas will deter them from entering. This myth is blatantly untrue. There is no evidence that cucumbers repel roaches; in reality, you’ll just be giving them more food and incentive to invade your home.
Boric acid is a colorless, crystalline, white powder made from boron, hydrogen, and oxygen. It’s used as an antiseptic, flame retardant, and insecticide. Boric acid is harmless to both people and pets, but when consumed by roaches, it damages their nervous system, making it a lethal pesticide.
This mineral is a naturally occurring sand extract that is the remnants of fossilized algae and is composed mostly of silica. It sees use in healthcare, construction, agriculture, and even explosives. Diatomaceous earth is a popular natural remedy for garden pests and often sees further use as a roach killer. It works by destroying their exoskeletons and can be applied outside the home, acting as a perimeter defense, or sprinkled where roaches are known to frequent.
Countless online sites espouse the insect-killing powers of peppermint oil, claiming it can repel everything from bed bugs to fleas, spiders, and, of course, roaches. The truth is that few essential oils have any impact on insects. Those oils that are shown to deter pests are short-lived and require constant reapplication, making them unfit as long-term solutions. In general, we don’t recommend using essential oils for cockroach control.
While DIY solutions may help eradicate small numbers of roaches, they’re typically ineffective against full-blown infestations. Roaches are hardy, sneaky creatures, often residing in homes for extended periods before most residents become aware of them. Roaches also multiply rapidly, making complete eradication difficult. Furthermore, home remedies for roaches take time to work or require direct applications to kill, making progress slow. As a result, most of the solutions on this list are ineffective at clearing up large-scale roach infestation. If you’re experiencing a full-on roach infestation, your best bet is to contact a professional pest control company.
Roaches are some of the nastiest household pests that plague homeowners. They’re difficult to kill, carry dangerous diseases like E. coli and salmonella, multiply quickly, and are known to infest entire buildings. Thankfully, there are plenty of effective DIY solutions for taking down these revolting insects. But remember that many of these roach baits, sprays, and insecticides are only effective at dealing with, at best, small cockroach infestations. You should always contact an exterminator if you’re experiencing serious or prolonged roach problems.
Other Pest Resources