How to Make Organic Roach Killer

Kill or deter cockroaches with a number of safe substances, including diatomaceous earth, baking soda, boric acid, dish soap and catnip.

An integrative cockroach management program starts with excluding roaches from the places in your house they frequent. You do this by sealing the openings through which they pass and eliminating the food and moisture that attract them. If you already have a roach infestation, however, these methods aren't enough to bring it under control; you must include strategies to actively deter and kill existing roaches. There are several ways to do this without resorting to chemicals that can harm you as much as they do the roaches.

Three White Powders

Baking Soda Bait

Pest experts, including Stephen Tvedten, claim that baking soda kills cockroaches. It probably reacts with the water and acids in a roach's stomach to create a toxic gas that kills them. Take advantage of this property of the household deodorizer to make a bait that you can spread in dark corners of cupboards and drawers and under cabinets. The recipe is simple: mix equal parts of baking soda and powdered sugar and add 10 percent powdered yeast. You can either deploy this mixture in trays or mix it with water to make a paste that you can form into balls.

Boric Acid Bait

Boric acid works differently than baking soda -- it interferes with the digestive processes in a mechanism that isn't fully understood. Nevertheless, its efficacy is unquestioned, and it's available in many commercial formulations. It's easy to make your own bait -- a simple way to do it is to mix boric acid powder with sweetened condensed milk to make a paste. Form the paste into balls and deploy them in places where you've seen roaches.


Although boric acid is considered to be of low toxicity, it could be dangerous for children and pets, so keep it out of their reach.

Dusting with DE and Boric Acid

Putting a fine layer of boric acid in the path of marauding roaches forces them to walk through it, and when they preen themselves, they'll ingest the chemical and die. You can use the same strategy with DE, but its action is to dry out the carapaces of the creepy varmints. In both cases, it's essential to keep the layer as thin as possible, so apply the dust with turkey baster or by using a squeezable plastic bottle. The layer must be virtually invisible, or the roaches will avoid it.

Pest experts recommend two readily available white powders for cockroach control -- baking soda and diatomaceous earth -- and, if you're willing to tolerate a slightly toxic substance, you can add boric acid to the list. Baking soda and boric acid can be turned into effective baits; you can also dust with all three powders.

Alternate Control Methods

Extermination expert Rick Steinau recommends keeping a bottle of soapy water nearby and spraying roaches whenever you see them. This treatment repels and also kills the insects. In addition, Steinau recommends brewing strong catnip tea and spraying this in areas where you see roaches -- they dislike nepetalactone, one of the ingredients in catnip, and will avoid the sprayed area. Avoid this method if you have cats -- you'll drive them crazy.

If you'd rather avoid chemicals altogether, Tvedten suggests waiting until the sun goes down, then illuminating the infested area with a dim red or yellow light and vacuuming up all the roaches you see. Add a teaspoon of cornstarch or talcum powder to the vacuum bag to kill the insects that you manage to snag.