PSA for people with cockroach problems: Diatomaceous earth is a lifesaver! Non toxic, (also a good fertilizer for the garden) and keeps working until it gets wet.
What is it? fossils of diatoms in a chalky-powder what do you do with it? Sprinkle (dusting) into hard to reach areas (think behind & under kitchen equipment, drawers, along baseboards)
what it does is sticks to anything with an exoskeleton & dehydrates them..they die.
https://en.m.wikipedia.org/wiki/Diatomaceous_earth
we live in a humid, costal town where they are endemic and we have ZERO of these motherfuckers in our shop & home