[quote=spdrun]Borax. (Assuming no pets or kids who lick the floor.)[/quote]
I have heard of using Boric Acid baits. While I haven’t used them on roaches, I have used them on ants and they were very effective where other things failed. Boric Acid is relatively harmless to humans and animals, however it is toxic to insects and can bio-accumulate in insects. Because roaches are cannibalistic, they will consume their own dead which may have been killed by Boric Acid – which then continues its effect. It is not an instant insecticide, it takes time but tends to wipe out large populations. Some people have even recommended using the sonic devices to drive the roaches away from most rooms and towards a ‘killing room’ that has the Boric Acid bait.
NOTES:
It is possible to buy Boric Acid based ant and roach killers – and is relatively cheap.
Not recommended for kitchens unless it can be secured away from food prepping areas.
If making your own Boric Acid bait, you want the concentration of the Boric Acid at between 1% and 3%. Too high and the insects will not consume it.
When setting the bait out, it will look like you have rung their dinner bell. If not, your concentration of Boric Acid may be too high or the ‘attractant’ – which is often sugar water/gel is mixed wrong. If they come, keep setting out the ‘dinner’. It will take several weeks – then they start dwindling in appearance. Keep supplying until none show up.
Don’t use ‘glue traps’ when using a bio-accumulative ‘bait’ trap. The glue trap will prevent the roach from taking it home.. sharing it, or being consumed by another roach when it dies.
