What type of treatment should be used for German cockroaches in a cupboard?

For German cockroaches in a cupboard, a chemical crack and crevice treatment is the most effective choice. This method targets areas where cockroaches are likely to hide and breed, such as in the tight spaces and crevices commonly found in cupboards. Applying insecticides in these targeted areas allows for a more localized treatment, which minimizes exposure to other surfaces and reduces potential risks to humans and pets.

Chemical crack and crevice treatment is advantageous because it can effectively reach the harborage sites of cockroaches, enhancing the likelihood of contact with the insecticide. This method allows for precise application, decreasing the amount of chemical needed and focusing on the roaches' specific hiding spots rather than treating the entire area with broader methods that may be less efficient or more hazardous.

Other treatment options, such as fogging, generally scatter insecticides throughout the area and may not effectively target the hidden cockroaches in cupboards. Spot treatment might miss infested areas as well, while liquid surface sprays are better suited for treating exposed surfaces rather than cracks or crevices where cockroaches tend to reside.