Cockroach Control Using Boric Acid

Boric acid isn't non-toxic, but it isn't as volatile as most insecticides, either. You can purchase it as a powder that you sprinkle in areas where you suspect roaches are congregating. It's not exactly organic roach control, but your roaches in house will get the boric acid on their exoskeletons through contact, after which the acid eats away at them until they die. Be sure to keep pets and children away from any area where boric acid is used.

Cockroaches typically become established in homes after being introduced in grocery bags, with laundry or, in some cases, wandering in from outdoors. Once cockroaches become established they are prolific breeders capable of producing several thousand offspring in a year.

Cockroaches prefer to live where there is food, warmth and moisture. Since cockroaches flourish where food and moisture are readily available, sanitation is an important step in prevention and control. Empty soft drink bottles, cardboard boxes and paper bags should not be allowed to accumulate. Food containers should be sealed and any crumbs or spillage cleaned up.

Unlike many household pests, cockroaches are prevalent year-round, causing homeowners and businesses to eventually seek some form of control.

Homeowners attempting to control cockroaches themselves will find boric acid effective and relatively easy to use. This factsheet will explain how to use boric acid to eliminate your cockroach problem.

People have been fighting cockroaches with boric acid for nearly a century. Boric acid is one of the most effective cockroach control agents ever developed provided that it is used correctly. Unfortunately, most people use it incorrectly, and in the process waste their money and effort.

Properties and Advantages

Boric acid is a wonderful tool for controlling cockroaches in homes, restaurants and other buildings. It is effective in extremely small amounts and retains its potency almost indefinitely provided the deposit remains dry. Unlike many insecticides, boric acid has no repellency to insects and, consequently, roaches return to treated areas repeatedly until they die. Boric acid is deadly to cockroaches, but is low in toxicity to people, pets and other nontarget animals. It is also odorless and contains no volatile solvents.

Boric acid is a white, inorganic powder chemically derived from boron and water. Boron is mined from vast mineral deposits in the ground and is used in countless consumer products, including laundry additives, toothpaste and mouthwash. Boric acid insecticide formulations can be purchased at hardware and grocery stores. The powder comes ready-to-use, i.e., no mixing or dilution is required. Formulations sold in plastic, squeeze-type bottles with narrow applicator tips are the easiest to use. (These containers are similar in appearance to the squeezable mustard and ketchup bottles found in restaurants).

Cockroaches succumb to boric acid when they crawl over treated areas. The tiny particles of powder adhere to the cockroaches' body, and the material is ingested as the roach preens the powder from its legs and antennae. Some boric acid is also absorbed through the greasy outer covering of the insect's body. All species of cockroaches are susceptible to boric acid provided the powder is applied into areas where the roaches are living.

Using Boric Acid Like a Pro

The key to success with boric acid is proper application. For best results, the powder should be applied in a very thin layer barely visible to the naked eye. Piles or heavy accumulations will be avoided by foraging cockroaches much as we would avoid walking through a snow drift.

Where the powder is applied is just as important as how it's applied. Cockroaches prefer to live in cracks, crevices and secluded areas close to food, moisture and warmth. Kitchens and bathrooms are the most common areas to find cockroaches, although any area of a home may become infested if the infestation is severe, or if species other than the German cockroach are involved. Key areas for treatment include under/behind the refrigerator, stove and dishwasher, into the opening where plumbing pipes enter walls (such as under sinks and behind the commode, shower and washing machine), and into cracks along edges and corners inside cabinets and pantries. Oftentimes, there is a void (hollow space) under kitchen and bathroom cabinets which becomes a hiding place for cockroaches. This area can be accessed and treated by injecting powder through any existing gap at the top of the kickplate, or if none is present, by drilling a few small holes.

NEVER apply boric acid onto countertops or other exposed surfaces, especially those used to prepare food. Any visible residues should be wiped off with a damp cloth. Boric acid can be used alone or in combination with other cockroach control products.

Borax (or Boric Acid) and Sugar

Borax is a very common household cleaning powder, widely available at grocery stores. Known scientifically as sodium borate, borax is a residual mineral found in locations where seasonal lakes have evaporated away repeatedly, such as in Death Valley and other desert plains.

Combined with a sweet bait material like powdered sugar or honey, borax has long been an organic means of killing ant colonies, and it also works to kill roaches. Apply the mixture along the baseboards, in cracks, under cabinets, under sinks, and anywhere else that you've seen roaches in your house. Reapply the mixture as needed until all the bugs are gone. If you prefer, you can put your roach killer out in little containers instead of dusting the surfaces of your home with it. That'll mean less mess and less chance of coming into contact with it.

Similar but even more effective results can be achieved by combining boric acid and powdered or other sugar. Boric acid is essentially a more refined form of borax, and while it is not as readily available, it's worth the effort to find it if you have a severe roach problem. Use it in the same way as borax—blend it with powdered sugar or another sweet substance (1/2 and 1/2), apply it as a bait in dark areas, and wait for roaches to ingest it.

Caution Keep this mixture away from children, pets, and food prep areas. Only apply borax bait in areas that your family and pets won't come into contact with. While this natural substance is not carcinogenic, borax should not be ingested or inhaled. Wear a mask when you apply the mixture and avoid inhaling it at all times. Accidental ingestion of small amounts is not very serious, but repeated ingestion can cause digestive problems and even organ damage. This is most likely if pets have repeated access to sweetened borax bait. The danger is more severe if you are using pure boric acid rather than natural borax.

Baking Soda and Sugar

Another fairly effective roach bait can also be created by blending ordinary kitchen baking soda and sugar. Sprinkle the combined mixture over surfaces where you want to bait the roaches—or set a small dish of the combined mixture in the target area—and wait for the roaches to consume it. While not as fast-working as borax bait, it will do the job if applied repeatedly over time.