Dear Umbra,

Help! I’m having a mysterious cockroach problem. I found four in my apartment in two weeks, and not in the expected places: one in a stack of papers (I know, I should pay my bills faster), one near my vitamin bottles, one nowhere near water in my bathroom, and, the worst one, crawling along the arm of my couch (while I was sitting on the couch). I don’t like to spray them with chemicals, but these things freak me out. How can I get rid of these beasties without poisoning my space (not to mention my cats)?

New York, N.Y.

Dearest Julie,

Grist thanks its sponsors. Become one.

Cockroaches have been around for hundreds of millennia, and will keep on keepin’ on long after our species is gone, as anyone at the journal Cockroach Studies could tell you. (Note to self: send cover letter, stat!) The good news is, there are scads of non-poisonous solutions.

How do I kill thee? Let me count the ways.

Photo: iStockphoto

Grist thanks its sponsors. Become one.

The best solution to a cockroach infestation is never to have one. (As they say: an ounce of prevention is worth a pound of roaches.) Effective prevention includes eliminating or minimizing moisture, food sources, and entry points for your insect friends. Be sure to drain sinks, tubs, and showers of standing water, regularly mop up condensation that collects under the fridge, and consider emptying your cats’ water bowl at night, when roaches are most active. Don’t keep food — human or cat — out, empty the trash often, don’t leave unwashed dishes lying about, and sweep and vacuum frequently. You might also consider caulking or otherwise eliminating gaps around drainpipes and the like to prevent the buggies from coming back.

All this work won’t necessarily get rid of your current gang (check out this lineup to see who you’re hosting). So I have a few more ideas for you, most of which will necessitate keeping a careful eye on your cats.

If you’re into peaceful approaches, you might be pleased to learn that catnip is a natural cockroach repellant, as is an inedible, softball-sized fruit called a hedgeapple. You can place these in known roach hotspots, sit back, and watch the diaspora.

Another option might be a simple trap. Roaches apparently love beer and bread, as well as cat and dog food. Place bits of bait in a wide-mouth glass jar, rubber-band some paper towels onto the outside for traction, and line the jar’s inner lip with petroleum (or un-petroleum) jelly to prevent escapes. Never tried it myself, but people more knowledgeable than I am swear that it works. Of course, you have to deal with them once you catch them. I suppose you could try relocating them, or creating some sort of educational cockroach farm for children.

Violent options include flushing, vacuuming, good ol’ blunt force, or filling a jar or spray bottle with dish detergent and hot water, which is apparently lethal to our little friends.

Two last non-toxic solutions are boric acid and silica gel. You’ll want to keep your cats away from these. Boric acid is a white powder that’s not toxic to humans (unless ingested), is inexpensive, and should be relatively easy to find. When a roach scurries across, the powder sticks to its legs. The acid is ingested when the roach cleans itself, and the poor thing croaks. One environmental downside is that most of the U.S. supply of boric acid apparently comes from an open-pit mine in Death Valley.

Silica gel can be made from sand and is also non-toxic by itself, though some common formulations include less innocuous additives. Overall, it’s much less toxic than spraying your house with chemical insecticides. It’s a desiccant, which means it absorbs moisture. And that’s how it kills roaches, by absorbing the waxes protecting their cuticles, resulting in death by dehydration.

Go forth and depopulate. And good luck.


Reader support helps sustain our work. Donate today to keep our climate news free.