How To Apply Diatomaceous Earth For Roaches. If it gets wet at all, this will affect how well it will kill roaches. A common application is to dust it under sink cabinets, stoves, refrigerators, and along baseboards.
Yes, diatomaceous earth can be used as an effective treatment for roaches and is exceptionally potent. Dry out any damp areas. Coat the powder around trash cans, bins, underneath cabinet trolleys, along edge of furniture in kitchen, window sills, door frames, patio etc.