How to Control German Cockroaches: Seven Steps to Follow When Facing a Roach Infestation

It is no secret that German cockroaches—those little bugs that could out-survive us in a nuclear blast—are notoriously difficult to eradicate from homes and apartments. They live in the walls. They live in and under ovens and refrigerators. They can even live in the microwave or coffee pot!

Eliminating an infestation, even at its beginning, can be a long, tedious, and expensive process, and those who cannot afford a professional exterminator may find themselves tearing their hair out and giving up. Plenty of affordable home remedies circulate around the internet, but which ones work best? Ultimately, treating roaches is a step-by-step process; no single treatment is going be enough unless the amount of roaches in a home is very small and limited to one area.

1. Find the Hiding Places and Entrances

Feces (black dots, akin to pepper) are evidence of roach activity. Feces and cast skins, as well as egg sacs (bean-shaped and brown), are evidence of a nesting area. Nests might be in appliances, such as ovens, microwaves, and refrigerators (even inside the refrigerator compressor and door, so check thoroughly).

If funds allow, and a nest in the refrigerator or oven seems large, it is highly recommended that one replace the infested appliances. However, the treatments listed below may completely eliminate the problem in such an appliance if given time, German roaches breed so rapidly that completely removing a breeding ground is preferable to treating it. This is especially true if the roaches have already infiltrated the mechanisms of the appliances, such as the refrigerator’s compressor.

However, roaches also nest in walls and enter through cracks and crevices. They may also hide (and attempt to nest) in many different places throughout a house. They hate moving air, so get a blow dryer (or other producers of moving air) and aim it toward all cracks, crevices, holes, and dark places to see if any roaches flee.

Take out all the books from bookshelves and check for evidence of their activity; they love paper because it retains the scent of their feces well. Throw away all cardboard boxes, which also retain their scent and provide ideal nesting places.

Move the refrigerator and oven away from the wall, if possible, to see if any are hiding beneath them. Pick up all clutter and keep the living area as neat as possible to reduce the amount of places roaches can hide.


2. Clean

It is a myth that only “dirty” housekeepers get roaches. This is especially true in apartment buildings in which a roach population already thrives (and is there to stay!). Cleaning alone will not solve the problem. However, this doesn’t mean that cleaning daily won’t have an impact on the number of roaches entering a home through the walls. Bleach the floors and counters daily, and vacuum carpets. Keep the drains clean of food residue and always wash dishes before going to bed, as roaches are more active at night and will flock to any food residue (especially grease).

3. Seal All Cracks

After cleaning, it’s time for the next, and probably most important, step: sealing entryways and hiding places. Remember those cracks and crevices identified as either hiding places or possible entrances in the first step? Buy several tubes of caulk and a caulking gun and proceed to fill them. Clear caulk is recommended for aesthetic purposes.

If a hole or crack is too large for caulking, use plaster or simply stuff it with steel wool. Duct-tape is also feasible; just remember that tape is not as effective (nor pleasing to the eye) as caulk. Plug all drains when not in use, as roaches may hide there.

While it may not be possible to seal every single entrance point into a home, simply blocking most entrances should be enough to effectively control the problem. Once an entrance (and nest) has been identified, other methods can be employed more efficiently.

4. Bait

Gel-baits are the quickest and easiest poison baits to use because they are more accessible than bait stations, which require the roach to enter them. The roaches will bring the poison gel back to the nest, thus reaching multiple roaches at once; because roaches are cannibals and will eat the poisoned bodies, a small amount of gel-bait can kill quite a few roaches. However, if the home has children or free-roaming pets, bait stations are probably a better choice, at least in exposed areas of the house. Check out the best roach baits at What is The Best.

5. Sprinkle Borax and Boric Acid

Lightly sprinkle 20 Mule Team Borax or boric acid under the refrigerator and bookcases, as well as inside kitchen and bathroom cabinets. Boric acid targets the nest and kills the way gel-baits do: slowly, and with extended results. When roaches walk through the powder, it sticks to their legs; they later clean themselves and die from ingesting it. Again, if the home has children or free-roaming pets, make sure to sprinkle it in unreachable places only. To learn more about killing roaches with Boric Acid, read here.

6. Use an Insect Growth Regulator (IGR)

Lastly, Insect Growth Regulators (most easily purchased online, as they are professional products) help to control a population and are especially effective if sprayed in or near a nesting area. Though an IGR will not kill roaches, it will prevent most roaches that come in contact with it from reproducing. For example, an IGR may prevent young roaches from growing into adults, or sterilize adult roaches. Simply spray the IGR where roaches have been spotted.

7. Spray and Fumigate

Spraying poison or fumigating (e.g. with bombs) should be the last resort, not the first step unless the population is already large and has infiltrated most areas of a house. Roaches run from such poisons—often into your neighbor’s apartment, or into other rooms and areas the poison cannot reach, which only spreads the problem. However, it can be helpful to spray a residual poison around a possible entrance as a preventative measure, such as under an apartment door or around windows and piping.

Use such poisons only in tandem with other treatments listed above; they will not remedy the problem when used alone.