Where should chemical pesticides be applied for the best results against cockroaches?

The most effective approach for controlling cockroaches involves targeting their harborages—places where they hide, breed, and find food and moisture. Applying chemical pesticides directly in or near these harborages maximizes contact with the pests and increases the likelihood of exposure to the insecticides. Cockroaches often inhabit dark, concealed areas such as cracks, crevices, and behind appliances, so focusing pesticide application in these locations ensures that the treatment reaches the insects where they are most likely to be found.

Other options, such as applying pesticides on surfaces exposed to sunlight, are less effective because sunlight can degrade certain pesticides, reducing their potency. High countertops may be less frequented by cockroaches, so treating these areas may not yield significant results. Similarly, applying pesticides in areas with heavy foot traffic could be problematic since those areas can disturb the treatment and make it less effective, while also posing a risk to humans and pets in the environment. Focusing on the harborages aligns with the principles of Integrated Pest Management, which emphasizes pest monitoring, habitat modification, and targeted treatment for optimal control.