What’s the best way to kill cockroaches?

Illustration by Slug Signorino

Cecil replies:

Calm yourself and pay attention to your Uncle Cecil. There are two proven approaches to dealing with la cucaracha: (1) borax, and (2) arson. Assuming your landlord objects to the latter line of attack, hie yourself down to the basement and mix up the following recipe: 4 parts borax, 2 parts flour, and 1 part cocoa powder.

Now, you may regard borax as “pansy-ass,” but that’s because you’re young and ignorant and haven’t yet grasped the subtleties of Total Insect Warfare, which requires fanatical dedication. You must mix up oodles of this stuff and apply it with the enthusiasm of Robert S. McNamara dumping Agent Orange on the Mekong Delta. Pour it in a continuous line along the walls. Put an extra dose under sinks and around kitchen cabinets. Hell, fill your damned house to a depth of one foot with the stuff. The little bastards will die piteously, I promise.

Incidentally, should you also be happen to be troubled by rats, I have here an ingenious formula for inducing rat death: Mix equal parts cement and flour. Place a pan of this powder out next to a pan of water. The rats eat the cement, then they drink the water, and by the next morning their bowels have turned to concrete. Sadistic, eh? I knew you’d love it.

Field reports from the Teeming Millions, part 1

Dear Cecil:

With regard to your answer to the cockroach problem, there’s an easier way. The cocoa powder mixture is rather messy and probably sticky with excessive moisture. What you should do instead is get DAP putty and some steel wool. Put the steel wool in every (and I mean every) hole you find in your apartment. Seal well with the putty or even cement. After all, if the roaches can’t get in, you don’t have to worry about killing them. The roaches eat the steel wool to get to you and die of a very bad case of indigestion.

If that isn’t enough, apply Roach Prufe powder (about $8 a can). This miracle powder works like a charm because it sticks to the little varmints and they take it back to their homes and kids, where they lick the stuff and die. What’s best is that the roaches don’t recognize this light blue odorless powder as poison.

Death to roaches.

— R.S., Baltimore

Dear R.:

Listen, doofus, what do you suppose is the active ingredient in Roach Prufe? Boric acid, that’s what. What did I tell you to dump all over your house to kill roaches with? A mixture containing borax, which for our purposes is equivalent to boric acid. Now, if you use Roach Prufe, it’ll cost you a jillion dollars to get enough to do the job right. If you use my method, and mix up some generic Roach Prufe, so to speak, you’ll save beaucoups bucks. It’s people like you that make me despair of ever rescuing this country from the clutches of ignorance.

Field reports from the Teeming Millions, part 2

Dear Cecil:

This young and ignorant 39-year-old, who has tried (among other things) the three poisons most used by professionals against roaches, has tried your borax stuff for two weeks. The problems are (1) the gritty junk gets tracked all over the house; (2) if it gets wet it forms a dark crusty mess (not easy to avoid around sinks and tubs), (3) there have been no dead bodies, and (4) there have been more live bodies. I wrote you for the Straight Dope — not more pansy-ass folklore. Please try again.

— Hayden J., Chicago

Dear Hayden:

Two weeks? Two lousy weeks? Hayden, for Jah’s sake, we’re talking about eradicating a bug that has lived on this planet for three hundred million years. Have a little patience. In the meantime, caulk those cracks with steel wool, per recommendation of R.S. (see above).

Field reports from the Teeming Millions, part 3

Dear Cecil:

In view of the constant criticism you’ve been receiving concerning your surefire roach-killing concoction, I felt I should write. We tried it, and at first the results were discouraging. But gradually we noticed an improvement in the situation. I don’t know if the little buggers died or not, but they’ve stopped frolicking in and around my living quarters. The mixture does work, but, like all boric-acid-based mixtures, including Roach Prufe, it needs time to take effect.

However, as Hayden J. points out, it does make a helluva mess when it gets wet.

— Patricia L., Chicago

Dear Patricia:

Thanks, Mom.

Field reports from the Teeming Millions, part 4

Dear Cecil:

I imagine you’re getting a little tired of this topic, but I thought I would write in with one more comment about cockroach extermination. The only way to succeed is to be persistent and use all the methods. First, find all the holes in the apartment (especially the bathroom and kitchen) that lead to another apartment. Caulk them up tightly. Cockroaches need water, so never leave water in the sink or dirty dishes anywhere.

Put boric acid around the baseboards and especially around the sink. Put Roach Motels (they do work) under the sink and/or on the counter near the sink. There are also small black strips that can be put in places that cockroaches walk, which will poison them when they cross. And don’t give up looking for entrances from other apartments, because roaches can leave a trail for others to follow.

One last point about boric acid. I heard it gives the roaches indigestion, they can’t fart, and so they explode!

— Rufus B., Baltimore

Dear Rufus:

They explode? Where do you guys come up with this stuff? I have two possible explanations for what borax does, both given to me by reputable scientists. Take your pick:

1. The stuff gets on the waxy coating on the critter’s hide (or “exoskeleton”) and partially dissolves it, whereupon the cockroach dehydrates and croaks.
2. The borax acts as an abrasive, causing microscratches in said coating. Cockroach dehydrates, etc.

Inasmuch as the Teeming Millions have doubts about the efficacy of borax, I should mention there’s a more drastic method for those preferring the take-no-prisoners approach. Unfortunately, it also renders your house temporarily uninhabitable, so I have qualms about recommending it. It’s called a “carbamate bomb,” carbamates being a class of particularly deadly bug poisons. You seal up your house, light the “bomb” (it looks and works something like a roadside flare), and scoot out the door. The fumes from the bomb kill every living thing, and 48 hours later, if you’re lucky, you can move back in.

The drawbacks are that the bombs are expensive, you have to stay with friends for a couple days, and after you move back in you have to swab poison off every exposed surface. In addition, if your slobbola next-door neighbor doesn’t improve his housekeeping practices, his cockroaches will just migrate over to your place and two months later you’re back where you started. Personally, I think you’d be better off sticking with borax.

Cecil Adams

Send questions to Cecil via cecil@straightdope.com.