Australian cockroaches in Florida

The Australian cockroach is one of the large roaches Floridians call palmetto bugs. Along with the American cockroach, it’s the most common large outdoor roach DNR finds inside homes, and UF/IFAS calls it the most common cockroach found outdoors in southern Florida. Adults are about 1¼ to 1⅓ inches long and reddish-brown to dark brown, with fully developed wings they use to glide.

Australian or American cockroach?

The two look very similar. The easiest way to tell them apart is the light yellow streak along the outer edge of each wing, near where the wings attach. American cockroaches don’t have it. Australian cockroaches are also a little smaller than adult American cockroaches.

Where they live

Australian cockroaches live mostly outdoors in moist, sheltered spots: under tree bark, in firewood piles, mulch and leaf litter, and around greenhouses and potted plants. They wander indoors, especially in cooler weather, and hide in warm, dark, damp places like under sinks, around water pipes and toilets, and in cupboards.

How to keep them out

1. Install tight door thresholds and sweeps. UF/IFAS notes a gap the width of a quarter is enough to let them in. Stand inside with the lights off and look for daylight around doors and windows.
2. Move firewood and woodpiles away from the house.
3. Pull mulch and leaf litter back from the foundation, and fix leaks and AC condensate drips.
4. Run water in sinks, tubs and showers that aren’t used often at least once a week.

How DNR treats Australian cockroaches

Like American cockroaches, they come from outside, so we start there: treating the perimeter, mulch beds, woodpiles and other outdoor harborage, and sealing the entry points they use. Inside, we treat the areas where they hide. Call 727-594-0404 or book a free consult.

Related pest spotlights: Palmetto Bugs vs. Cockroaches and American Cockroaches.

FAQ

Is an Australian cockroach a palmetto bug? Yes. “Palmetto bug” is a Florida nickname for several large outdoor roaches, including the Australian cockroach. See our Palmetto Bugs vs. Cockroaches page.

Do Australian cockroaches infest homes? They mostly live and breed outdoors and wander in, unlike German cockroaches, which live and breed indoors.

Can Australian cockroaches fly? They have full wings and can glide, but they’re not strong fliers.

Source: University of Florida/IFAS Featured Creatures, Australian cockroach, Periplaneta australasiae. Reviewed by Ricky Williams, Certified Operator in Charge.