To rid your home of German cockroaches, follow these five steps.
1. Identify the Problem
Although many roach control methods are effective against most cockroach varieties, it’s always a good idea to confirm exactly what kind of insect you’re dealing with. You’ll also want to see if you can identify the hot spots in your home. German cockroaches don’t create a central nest or hive, but they will be more active around heat, water, and food sources.
You can conduct an inspection by walking from room to room with a flashlight, looking in cracks and along baseboards for evidence of roach activity. Although you may not see live roaches during the daytime, you may see droppings, shed skins, or dead roaches. Look closely in kitchens and bathrooms, especially inside kitchen cabinets and behind appliances and furniture where roaches may hide.
If you can’t stomach the idea of such a close inspection, you can use sticky traps instead. Place these under sinks, in corners, behind appliances, and near trash cans. Although these will only catch and kill a few roaches and are ineffective against a larger infestation, they will give you a good idea of where roach activity is highest. Then, you’ll know the specific areas of your home to target in the next step.
2. Clean Areas of High Roach Activity
The idea here is to get rid of competing for food and water sources so the bait you lay for the cockroaches will be more enticing. However, don’t use any harsh or strong-smelling chemicals. Vacuum crumbs and debris, clear away clutter, package food in airtight containers, and wipe down surfaces with dish soap. Additionally, if you end up vacuuming any live roaches or eggs, make sure to seal and dispose of your vacuum bag or place it in the freezer for a few hours to kill anything living inside it.
3. Set Out Bait
There are two main methods of chemical cockroach control: sprays and bait stations. Sprays either repel cockroaches or kill them on contact. Bait stations and gel baits lure cockroaches in with poisoned food and get them to take the bait back to their nests. Gel baits can be squeezed into smaller cracks where bait stations can’t fit. The slow-acting insecticide will allow the cockroaches to infect others, hopefully eliminating most or all of the roach infestation.
We recommend this method over using sprays. Repellent sprays will only succeed in driving the roaches back into hiding, allowing them to continue to reproduce. Contact insecticides will only kill the roaches that you see or that step on the areas you spray, which won’t stop the problem at its source. In particular, don’t use sprays after laying down bait, since the roaches that take the bait need to survive long enough to spread it.
4. Determine Whether More Insecticide Is Necessary
Although sprays and bait are most common, there are other types of cockroach control that you can try if bait stations aren’t sufficient. Insecticide dust like diatomaceous earth, boric acid, or synthetic formulas can get into cracks and crevices that even gel bait can’t reach. However, if you’re still using bait, make sure not to apply the dust around the bait stations, as you’ll be working at cross-purposes.
Additionally, a product called insect growth regulator (IGR) can actually stop roaches from reproducing. This substance is a liquid or aerosol foam that stops cockroach nymphs from shedding their exoskeletons and reaching reproductive maturity, breaking the breeding cycle. This is a slower-acting form of insecticide that works best in conjunction with bait.
5. Prevent The Cockroaches From Coming Back
Once you’re confident that you’ve eliminated the bulk of the infestation, it’s important to get rid of the conditions that made your home roach-friendly. When you’re getting rid of German cockroaches, you can’t be too clean.
If you prefer to use bleach or ammonia—though never at the same time—to clean hard surfaces, now’s the time to do it. Give your kitchen and bathrooms the deepest cleaning treatment, making sure to also double-check that all food sources are sealed.
As you go along, make sure you fix any leaks or drips that leave behind standing water. Seal cracks and crevices along windows, doors, and utility pipes with caulk or other sealants to prevent roaches from getting in. Switch to a trash can with a tight-fitting lid for food waste. Air out or dehumidify basements or crawl spaces to keep moisture from building.
You also may need to make some adjustments to your cleaning schedule. For example, make sure you take care of dirty dishes as soon as possible and wipe down countertops to clean away food or beverage spills immediately. Clean out refrigerators regularly, and take the trash out whenever there’s food waste inside. Vacuum frequently to get rid of crumbs as well as any stray cockroach eggs. In general, try to keep clutter to a minimum, as this can give roaches more places to hide.