Not only is peppermint oil a natural cockroach repellent—it's also toxic to roaches (and for the record, to bed bugs, too). The same Auburn University study found that mint oil killed both German and American cockroaches when they came into contact with it for an extended period.

Where do you put peppermint oil for roaches?

Diluting a few drops of peppermint oil with water and spraying it on walls or on cotton balls that you place throughout your home could effectively repel roaches.

What smells keep roaches away?

Cockroaches have an incredible sense of smell that they use to find food. You can take advantage of this fact by using scents they dislike such as thyme, citrus, basil, mint, and citronella to repel them from your home.