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G from Nj United States writes

How long until the Demon WP spray starts working?

I've only seen 2 dead roaches 5 hours after spraying Demon WP everywhere. One still alive and well in my dishwasher. They seem to like being in the dishwasher. How long is it supposed to take to kill the roaches? I am super neat and clean everything in sealed tight plastic baggies. All food is in baggies and in the refrigerator and the freezer. I sprayed everywhere even a little in inside wall plug ins. I sprayed in all holes, crevices, any small crack and crevice. How can they survive in my dishwasher? Yes, I sprayed in there too I couldn't stand it anymore. I sprayed under the dishwasher too. Pulled out refrigerator sprayed all over and under the stove. Shouldn't I see a lot of dead roaches by now? I sprayed at 11am today. Whats going on? I used 2 packets for one gallon of water. What's the story here?


Demon WP does not provide an instant knockdown of insects even if the insects are sprayed directly. You will see results over the next couple of days as the roaches come into contact with the treated areas and receive a lethal dose of the insecticide and they then succumb to the effects of the product. It is very important that you read and follow the product label to avoid contaminating sensitive areas. You can use a high quality roach bait gel such as the Advion Roach Bait Gel to treat areas where spraying would not be appropriate (counter tops, cabinets, drawers). The roaches will consume the bait and then go back to their nesting area and spread the bait which will help eliminate the roaches more quickly than spraying insecticides and IGRs alone. Getting rid of roaches is not a process that only takes only a few hours. Moderate roach infestations can take a few weeks to get rid of and severe infestations can take several months even when using all of the products needed (insecticide, IGR, roach bait) and sanitation is up to par.

Answer last updated on: 09/12/2011

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Demon WP Insecticide

Demon WP Insecticide

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