Untamed Lowcountry

Ew! 7 things you need to know about palmetto bugs (most importantly, how to get rid of them)

By Michael Olinger


Here in the Lowcountry, we share a common hatred for palmetto bugs (a.k.a. cockroaches with a fancy nickname).

“Usually when people are talking about palmetto bugs they’re talking about the smokybrown cockroach” said Eric Benson, Ph.D. professor and extension entomologist at Clemson University, who also listed American cockroaches as a species that gets tagged with the catch all term.

While both smokybrowns and Americans are referred to as palmetto bugs, Benson says that smokybrowns have the most legitimate claim to the name.

“If I look in the palmetto trees down on the coast I’m usually going to see smokybrowns as opposed to Americans,” said Benson. “If I look in a sewer or storm drain or commercial kitchen I’ll see American cockroaches first.

Here’s seven super important questions answered about the biggest pest of the Lowcountry:

1. What do they look like? Can they fly?!

Smokybrown and American roaches are similar in size and appearance. The American cockroach has a slight size advantage over the smokybrown, growing to lengths between one and a half and two inches, while the smokybrown usually tops out at an inch and a half. American cockroaches are reddish brown with a pale margin behind their head, while smokybrowns are darker and more uniform in color.

Both smokybrown and American roaches can fly, sort of.

“Lots of times when I see them, they will be gliding down from a higher location,” said Benson, who noted that their gliding can be confused with flight by some. “They can fly, but they’re not great flyers.”

2. Where do they typically live and lay their eggs?

Palmetto bugs prefer to live in areas that are moist and humid, a huge contributing factor to why they are so prevalent in the Lowcountry. Places you are likely to find them around your home include:

  • Bathrooms
  • Kitchens
  • Attics, especially in attic corners
  • Crawlspaces
  • Under sinks
  • Behind dishwashers
  • Under refrigerators
  • Sceptic tanks
  • Trash bins/dumpsters
  • Mulch
  • Gardens
  • Leaf litter
  • Trees

These are also the places where they prefer to lay their eggs according to Benson, as females choose places for their eggs that provide protection, are moist, and near food.


3. How the heck do I keep these things out of my house?

Palmetto bugs can get into homes in any number of ways.

“If you’re an inch long and you can flatten down to the width of a quarter or less, there’s almost an infinite number of ways you can squeeze into a home,” said Benson.

The best ways to keep the troublesome pests at bay include keeping doorway thresholds in good shape, with no gaps under the doors, putting screens on doors, windows, and attic vents, sealing up any cracks that lead into your home, and making sure that there are no gaps around anything that goes through an external wall, like pipes and cables. Excessive mulch can draw palmetto bugs to your home, as can food and water left outside for pets.

4. Are palmetto bugs dangerous?

Palmetto bugs can pose health risks. They serve as hosts to any number of harmful pathogens, including salmonella, which can contaminate food, leading to illness.

“They can live in unsanitary areas. So if a cockroach comes out of a sewer drain, and then walks up and crawls over your plate or your food, they could spread germs that way,” said Benson.

Beyond that, the debris they leave behind, including feces and sheddings contain proteins that can trigger asthma attacks and allergic reactions, especially in the instance of smaller German roaches.

Palmetto bugs have also been known to bite, which can cause skin irritation.

5. Are they really a sign of filth?

While the perception of palmetto bugs is that they are harbingers of filth and an indication that you might need to take your next cleaning day a bit more seriously, that isn’t the case.

“It has nothing to do with cleanliness or the economic conditions of the area,” said Benson. “They could be around the nicest home or the nicest hotel or resort.”

Palmetto bugs aren’t looking for filth so much as they are food, and they eat practically anything. Your nicely mulched garden is just as appealing to them as the overflowing dumpster a few blocks away.

6. What kills them?

There are many common insecticides that are effective against roaches. They contain chemicals like cypermethrin, cyfluthrin, deltamethrin, or bifenthrin.

Roach baits contain active ingredients like fipronil, abamectin, or hydramethylnon and are effective as well, as is boric acid dust.

Benson recommends against the use of foggers, also known as bug bombs.

“Those foggers just throw insecticide out all over your room,” said Benson. “But those things often don’t get into all the cracks and crevices where the roaches are hiding.”

7. When should I call an exterminator?

Deciding when to call in reinforcements to deal with your palmetto bug problem is a personal choice according to Benson.

“I would say if you see a cockroach and you don’t want to see a cockroach, consider calling a pest management professional,” said Benson. “People are going to have different tolerance thresholds.”

There are some variants of roach that are more likely to infest a home than others, like the German cockroach, which is smaller than the American or smokybrown and can vary in color from tan to black. If you see one of them, it is usually best to get a pest control expert out to your home.

No matter what measures you take, palmetto bugs will remain a reality of life in the Lowcountry.

“You can control them. You can manage them. You can reduce their numbers as much as possible,” said Benson. “You’re not going to eradicate them or get them to zero.”