Where Do Cockroaches Hide in Kitchens?

First, Warm and High or Cool and Low

German cockroaches want warmth. They sit high and tight: inside and behind appliance casings, around the motor of a fridge, in the boiler cupboard, in the hinge recesses of wall units, behind a wall-mounted microwave.

Oriental cockroaches prefer it cooler and damper and stay low: under the sink, around floor drains and gullies, in the void under a kickboard, in a cellar, and in the bin store of a block. If you have searched the warm places and found nothing, search the cold wet ones before concluding you were wrong.

The Torch Method

Do it at night, an hour or more after the kitchen went dark. Take a torch and get low. Shine along the floor at the kickboard line first, then into the gaps beside and behind the appliances, then upwards into the recesses of the wall units.

You are looking for movement away from the beam, and for what they leave: droppings like coarse black pepper along an edge, shed skins in a crack, and small brown purse-shaped egg cases wedged under or behind things. The egg cases are the most useful find because they do not move and they prove breeding.

Pull the Appliances Out

The fridge is the single most productive place in a domestic kitchen: warm, undisturbed, with a condensate tray of water at the back. Then the dishwasher and washing machine, which have a casing void, water and heat all in one unit.

Cookers matter for the residue underneath as much as the heat. If you have never moved yours, that is where to start.

The Places People Never Check

Inside the hollow legs and plinth of a kitchen unit. Under the lip of a worktop where it overhangs a carcass. In the gap between two units where the filler panel is. Inside a coffee machine or a toaster. Behind a tiled splashback with a gap at the bottom. Inside the cable and pipe risers where they leave the kitchen.

In a flat, add the communal parts: risers, bin stores and ducting are how cockroaches move between properties, and a kitchen that is clean and still infested is usually being resupplied from outside it.

What the Search Is Actually For

Not so you can spray it. Gel bait goes into harbourage and along runs, and knowing where the harbourage is makes the difference between a treatment that works and one that does not.

Monitors then measure it. "We have not seen one this week" is not evidence — cockroaches are built to not be seen. The monitors are what tell you whether it is finished.