Both drought and rain draw cockroaches indoors in NC. How to keep them out
AI-generated summary reviewed by our newsroom.
- Drought conditions drive cockroaches indoors as they seek water and shelter.
- Peridomestic smokybrown cockroaches enter via doors, soffits, gables, windows.
- Label violations for insecticides are federal offenses; professionals are recommended.
When the weather is severe, many insects want to come inside to find water or stay safe. As drought conditions persist, roaches are more likely to enter your home.
NC State Assistant Professor and Extension Specialist Christopher Hayes said outdoor roaches are looking for a secure environment.
“Anytime you have kind of severe weather on either side of the spectrum, either severe drought or severe flooding, it drives insects into safe spaces and more resource secure spaces,” Hayes said. “If it’s a drought, a cockroach is going to need water. A great place to find water is in our homes.”
There are more than 5,000 types of roaches, and 60-70 are found in the United States, according to the North Carolina State Extension.
Types of roaches
Hayes said people will most likely come across peridomestic cockroaches like the smokybrown cockroach. Peridomestic cockroaches live outside but frequently make their way indoors. Domestic cockroaches, like the German cockroach, live inside.
Cockroaches can carry bacteria, but their potential as a vector is not understood well.
“There is some evidence that German cockroaches can transmit disease on their body,” Hayes said. “But the biggest thing that we are concerned about in terms of cockroaches, and this is also true for bed bugs, is they are major depositors of allergens in the environment.”
Between 17-41% of people in the United States are allergic to cockroaches, according to The Asthma and Allergy Association of America. Symptoms include sneezing, runny nose, itchy skin and coughing.
Smokybrown cockroaches are often also called palmetto bugs and water bugs, according to the NC State Extension.
How to keep them out
To keep roaches out, you need to know how they get in.
“At night, step outside and look at your door. If you can see light coming through it, pests can get in,” Hayes said. “If you see light around the base of your door that’s creeping out, it’s probably a big enough gap that a cockroach could squeeze through.”
Cockroaches also get in through soffits, gables, cracks, windows and unsealed garage doors.
Glue boards can catch roaches, but they should be kept away from children and pets. If glue gets onto an adult or child, oil can be used to get it off, Hayes said.
Residual insecticides are another option, but should be handled with care. The insecticides are typically formulated to be sprayed.
“I always like to remind people a label violation on an insecticide is a federal offense. The label is a federally mandated law,” Hayes said. “It’s always a big deal to violate, but people don’t think about that, they’ll just kind of put stuff wherever they want and not consider waterways or drainage or wells.”
Hayes recommends hiring a professional to handle residual insecticide options if possible.
