Mix equal parts water and dish soap in a spray bottle and spray it directly onto the cockroach. The soap will suffocate the insect, killing it instantly. However, it's important to note that soapy water is only effective when applied directly to the insect and may not be as effective as other methods.
If cockroaches get enough borax on the outside of their bodies, it actually damages their exoskeletons. This causes them to rapidly dehydrate and die; a thick coating of borax will certainly get rid of roaches overnight.
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.
One popular DIY method is to mix boric acid with equal parts powdered sugar as a lure. Apply as a fine layer under appliances, behind cabinets and along crevices. Roaches ingest the mixture and die within a few hours.
Unfortunately, bleach is a very ineffective method for killing cockroaches. It has a very strong smell, so it doesn't work as bait, and cockroaches won't willingly go to it. The only real way to kill a roach with bleach is to drown it, and there are much more effective ways of killing cockroaches.
The Combat Roach Killing Bait is our top choice among roach killers. It's inexpensive and easy to use—just place the bait stations on surfaces and in corners where you have seen insects lurking or suspect they might have been.
Boric acid tops even baking soda when it comes to killing cockroaches. With little more than a sprinkle on the floor, boric acid acts as an all-natural poison to take down dirty roaches in just days. Or, spread a dusting on a paper plate and bait it right in the middle with a piece of orange peel.
Boric acid can quickly kick a roach infestation to the curb. It's extremely toxic and can kill multiple generations of roaches. Mix a combination of equal parts of boric acid, sugar and water to make a dough. Roll that dough into balls or cylinders and place them where roaches will find them.
Cockroaches are most likely to be active about four hours after dark and enter a period of immobility just afterwards. This immobility period is similar to what humans would call “sleeping.”
Diatomaceous earth is a great choice when it comes to killing cockroach eggs. We recommend trying this method when you are sure there is already an ongoing infestation in your house. It's made of marine phytoplankton, which is toxic to roaches and can dehydrate the ootheca. Make sure to buy the food-grade version.
Sprinkle the diatomaceous earth around areas where roaches travel and frequent. The sharp particles of diatomaceous earth damage the waxy, protective exoskeleton of the roach, causing it to dehydrate and die, typically within 48 hours of contact.
Roach Repellents
Peppermint oil, cedarwood oil, and cypress oil are essential oils that effectively keep cockroaches at bay. Additionally, these insects hate the smell of crushed bay leaves and steer clear of coffee grounds. If you want to try a natural way to kill them, combine powdered sugar and boric acid.
It's a fact that cockroaches are afraid of humans and other mammals or animals that are bigger than them. They see us as predators and that fear triggers their instinct to scatter away. However, they dislike strong and distinctive scents such as citrus, peppermint, lavender and vinegar.
Taking a deep drink of household bleach would kill anything, roaches included. But the same strong odor that keeps people from taking a swig of bleach repels roaches as well. So though it could work, in reality, it will not. It is very difficult to kill an entire roach infestation yourself.
Roaches are attracted to similar things as any other pest: shelter, food, and water. Anything that makes these things more available and easy to access is going to contribute to a roach infestation.
Two of the most common cockroach predators are toads and frogs! Both of these amphibians are known for eating insects like flies, but they also gladly welcome cockroaches.
Boric acid
Boric acid is a powerful natural home remedy for getting rid of roaches overnight. Mix equal amounts of boric acid, flour, and sugar until it becomes a dough-like consistency. Place small pieces where the roaches can feed on them.
The most common places for a roach nest in the house are in kitchens or bathrooms, particularly behind refrigerators, in cracks and crevices, and under furniture. Roaches prefer a warm, humid environment, so these places should be considered first, especially if they are close to a food source and water supply.
Spraying window cleaner directly onto small insects like ants or mosquitoes will kill them within a few moments. For cockroaches, window cleaner can make them temporarily unconscious so that you can squash them. This works on initial contact, but Windex will not continue to kill bugs after it has dried.
Windex can kill cockroaches, but only if you twist the nozzle to stream mode and spray it directly, full-strength on a single insect for at least a minute. We give it a 3/10 on our effectiveness scale.
All About Vinegar
Unfortunately, it doesn't actually kill these problem insects. It's more of a cleaning tool than anything else, and it won't actually help eliminate your roach problem. It can, however, help deter roaches and get rid of germs in the kitchen when used as a cleaning agent.