Few household pests inspire more loathing than the seemingly indestructible cockroach. The infestation may begin slowly, but soon enough you’ve got a swarm. Turn on the kitchen lights to grab a midnight snack and there are the vermin, scuttling for cover. And if you’ve ever seen three-inch American cockroaches (aka waterbugs) fly out of your bathroom sink, it’s something you never want to see again.

Yuck factor aside, cockroaches in the home are a health hazard. They don’t just carry germs and spread disease; their droppings and cast-off skins can exacerbate allergies and asthma, especially in children.

You may spot signs of cockroaches — such as little brown dots (droppings) on cereal boxes or paper, and small brown ovals (egg casings) — before you ever see one. These signs, or spotting even a single cockroach, mean you need to take some fast action.

“For every one you see there can be many, many more hiding and multiplying behind your walls,” according to the pest control company Orkin.

How to get rid of them (and keep them gone)? Try these inexpensive and natural strategies, courtesy of the Environmental Protection Agency (EPA) and pest control experts, before you call an exterminator.

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Clean your home. Then clean it again. Cockroaches are attracted to food and moisture. In the absence of either, they will crawl somewhere else. Seal all food in airtight containers and clean your dirty dishes promptly. Keep appliances and cooking utensils clean as well or you may have cockroaches feasting on last night’s spilled stew on the stovetop. “The worst cases we see, the house is usually a mess,” says Mark Koontz, owner of AK Pest Control in Virginia. “But roaches will come in any way they can if you leave food out.”

Seal up cracks and crevices, especially in the kitchen. Check inside cabinets, the pantry, between countertops and walls and along the baseboards. Caulk all cracks and holes around faucets and gaps between the wall and pipe fittings.

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Fix any water leaks. Since cockroaches need water, they’ll head for any source of it they can find. If you have leaky faucets or seeping water in the bathroom, call a plumber.

Limit eating and snacking to the dining room and kitchen. Cockroaches will appreciate any crumbs or popcorn dropped in the living room as you snack in front of the tube.

Make your own non-toxic roach killer. “Boric acid works well in getting rid of them, but you’ve got to bait it with a food source or a pheromone additive to attract them,” says Koontz. Here’s what he recommends:

  • Buy powdered boric acid (available at pharmacies), white flour and cocoa powder.
  • Mix one part boric acid, one part cocoa powder and two parts flour in a bowl. Add just enough water to give the mix a dough-like consistency.
  • Place small balls of the dough in areas where cockroaches congregate, such as near baseboards, inside cabinets, near windows and anywhere else you’ve seen them. The cocoa or sugar attracts the roaches, and the boric acid kills them. Flour simply holds the mixture together.
  • Replace the dough as necessary when it dries out, Koontz advises. This method may take up to two weeks to wipe out all roaches in a serious infestation. Keep children and pets away from this bait.
  • If you’d rather repel the roaches instead of killing them, you can place bay leaves or fresh slices of cucumber in the infested areas, according to pestexterminator.com. Roaches are repelled by their smell. Small packets of catnip are also effective for getting rid of roaches temporarily, according to the site.

Try the soap spray approach. If you spot “leftover” roaches, you may want to blast them with a solution from a spray bottle filled with equal parts water and dishwashing soap. This will suffocate them, according to Koontz.

If these methods don’t work, consider an exterminator. If you hire a pest control company, or if you plan to set off a bug bomb (fogger) on your own, check out these precautions from the Environmental Protection Agency.

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Steve Evans, MA, is an award-winning journalist with more than 20 years experience in daily news, investigative, health and business journalism. Among other jobs, he has served as managing editor of the Central Virginia Newspaper Group, as a senior writer for SNL Financial and as a staff writer for The Progress Index and the Richmond Times-Dispatch.