Home Remedies for Cockroaches: Fact vs. Fiction

Do home remedies for cockroaches really work? Here’s how to separate fact from fiction, based on our experience as the #1 highest-rated pest control company in New York City. Article by Joseph Salvatore Knipper from MMPC.

Do Home Remedies for Cockroaches Really Work?

Home remedies for cockroaches are often the first solution people look for when discovering these nightmarish pests in your home. After all, if household items are enough to keep cockroaches at bay, you can save yourself the time and cost of hiring a professional exterminator, right?

BUT, there’s a reason why you never see pest control professionals employing home remedies. Many of these “remedies” are unreliable or untrue, and some can even make your situation worse. Spending precious time trying home remedies that don’t work instead of calling the exterminator will give the cockroaches in your home time to quickly breed and multiply. This results in an infestation that gets harder and harder to get rid of.

Here’s a list of popular home remedies for cockroaches, along with our take on how much is fact versus fiction.

Bay Leaves: Mostly False

Bay Leaves are a commonly-cited DIY remedy for repelling cockroaches. Supposedly, if you sprinkle bay leaves in your garbage can or the corners of kitchen cabinets, roaches will be repelled by the smell.

It sounds natural enough—like something your grandmother would do. However, a search of scholarly articles for “Laurus nobilis” (the scientific name for bay leaves) and “Blattella” (the genus of the German cockroach) on the National Center for Biology Information revealed no articles about repellent properties of the leaves themselves. The same is true when searching for the genus of the American cockroach (“Periplaneta”).

The essential oil from bay leaves has the potential to kill certain pests, but this involves applying oil distilled from the leaves in such a way that insects are exposed to it directly. Scattering a few bay leaves just won’t do it.

Lemon Juice: Misleading

Another popular home remedy for cockroaches is cleaning your house with lemon juice and water. We agree that this is a good idea, but because of the cleaning part (see below), not because of the lemon.

Lemon contains limonene, which does in fact repel cockroaches. However, like with bay leaves, you’d have to obtain it in essential oil form at a sufficiently high concentration.

Furthermore, citrus essential oils are classified by essential oil connoisseurs as “top notes,” meaning they evaporate quickly. Technical grade limonene itself evaporates in 2/3rds of the time it would take the same amount of water to evaporate. For this reason, we’re very skeptical that either lemon or citrus essential oils are a satisfactory DIY method.

Cucumber Slices: Somewhat True

This home remedy tells you to place slices of cucumber around your kitchen to repel cockroaches. To us, this seems like giving cockroaches a free meal—a Benha University study found that while cucumber wasn’t a cockroach’s favorite food, it still attracted 1-2 of them over a 6 hour period.

But an Ohio Academy of Science study found that when cucumber slices were “well-crushed” they did indeed repel roaches due to several compounds found in cucumbers. However, this was only tested on a tiny 9 cm by 17 cm area, so there is no guarantee it would work on an entire apartment. 

We prefer to prevent the problem in the first place rather than leave small piles of crushed cucumber slices around the house.

Soaps and Detergents: Somewhat True

What about spraying cockroaches directly with soap or detergent? In terms of what to spray, some websites say laundry detergent, some say fabric softener, and some say dish-washing liquid. The latter was confirmed by this study, which found that 95% of adult German cockroaches could be killed by a 1% dishwashing soap solution in water. According to Kansas University, “The reason [soap] works is not well-documented,” but it does work.

However, in order for soaps or detergents to be effective, you still need to find and spray each roach individually. And they won’t die immediately either. Furthermore, most cockroach species in the New York area live in colonies, so killing a few with soapy water will still leave you dozens or even hundreds to go.

Isopropyl Alcohol: Somewhat True

Another commonly-found DIY remedy is to spray cockroaches with isopropyl alcohol. But because this isn’t a recommended form of pest control, there haven’t been many studies on the exact concentration needed to kill cockroaches. However, this is a less-than-ideal solution for several reasons.

First, the fumes of isopropyl alcohol can cause respiratory irritation, and are also highly flammable, making it not something you want to be spraying around your home willy-nilly. Secondly, you have to spray each roach directly, and roaches are fast at running away. Even if you manage to catch up to the roach, the larger species may be able to take squirt after squirt before they start to slow down.

To summarize, you might kill a roach or two, but isopropyl alcohol is dangerous and not terribly effective for an infestation.

Boric Acid: True

Boric acid is a fairly simple white powder sold as a DIY cockroach product. It is, in fact, effective at exterminating cockroaches, although please remember to follow all safety instructions when applying it at home. You could simply sprinkle it lightly along places roaches will walk, and it will cling to the roaches. When roaches groom themselves, they will ingest the boric acid and die.

Boric acid works best when the roaches eat it intentionally, and that means mixing it with things they like to eat. You can find several recipes online for making boric acid bait balls out of various ingredients you already have in your kitchen. Once again, please remember it is an acid marketed to kill roaches. Don’t use the same utensils and container to make the traps you are going to eat with later.

In the ideal scenario, cockroaches will eat the boric acid bait, wander back to their nest and die, and then other roaches will eat the poisoned roaches and die themselves. So don’t use boric acid bait at the same time you are using cockroach traps. Traps prevent poisoned roaches from returning to the nest to poison others.

Dryer Sheets: Mostly False

Dryer sheets are sometimes said to kill cockroaches if you lay them on the ground for the cockroaches to walk over. They are also said to repel them. While a single University of Kentucky study suggests dryer sheets do repel fungus gnats, we found no such study saying that they kill or repel cockroaches.

So where did this rumor originate? Linalool is an alcohol derived from plants, and it gives dryer sheets their distinctive scent. It can indeed be used as a pest repellant, but your average dryer sheet doesn’t contain enough of it to actually work on roaches.

The Best Ways to Get Rid of Cockroaches in Your Home

As pest control professionals experienced at dealing with cockroaches, here’s what we can say really works: you can stop or prevent cockroach problems before they even happen by removing access to food and water, reducing access to your home, decluttering, and cleaning.

These methods won’t necessarily eliminate an existing cockroach infestation, but they will help to keep things from getting worse while you call the exterminator.

  • Remove Access to Food and Water: One of the best things you can do to shoo away cockroaches is to remove their access to food. Invest in reusable storage containers that can be sealed and empty your trash and recycling bins regularly. Access to water is equally important; don’t leave any standing water around. Fix that leak under the sink, and mop up any puddles from the shower before you go to bed at night.
  • Reduce Access to your Home: While it’s hard to make a home 100% cockroach-proof, there are simple steps you can take to make your home more difficult to access. Install a door sweep on your outside door, stuff gaps around piping with steel wool, and repair cracks in your walls.
  • Decluttering: Cockroaches would rather not be seen by you. Decluttering reduces places they can hide, making it easier to spot when you have a problem. Keep the floor clear of clutter, organize under the cabinets, and throw out things you are no longer using. We know you are busy, but these simple steps can make a world of difference in pest control.
  • Cleaning: Cockroaches will chow down on hair, nail clippings, skin flakes, or even your paper and plastic bags. Cleaning is the number one DIY task you can perform to prevent cockroaches because it removes their sources of food. So if you really want to DIY your own cockroach solution, grab a sponge and a bucket of soapy water (lemon juice optional). 

While it’s hard to resist the temptation to try a few home remedies to get rid of cockroaches, once these pests get a foothold in your apartment, everyone needs a little help. If you live in New York City or the Tri-State Area and you need help exterminating a cockroach problem, give MMPC a call today.