The amount of time that it takes diatomaceous earth to kill insects varies greatly depending on factors such as particle size, temperature, relative humidity, the type of insect as well as the extent of the infestation.
Diatomaceous earth may need to be left down anywhere from 1 day to a week or more in order to be effective against an infestation.
Although each situation will be different, in many cases results have been seen with…
Bedbugs within 24 hours of properly applying the diatomaceous earth, with more substantial results after 5 days (120 hours).
Beetles such as Merchant grain beetles and Darkling beetles within 7-21 days. Note: for darkling beetles it is best to apply DE soon after manure removal in poultry facilities when mobility among the beetles is highest. This will ensure that the beetles come in contact with the diatomaceous earth.
Silverfish within 7-14 days. Note: the removal of clutter prior to treatment is recommended in order to improve effectiveness.
Black ants within 24 hours
Red ants within 16 hours
Be sure to monitor the infestation. Once you have reached the desired result, simply vacuum up the used food grade diatomaceous earth.
Note: it is important that you re-apply the DE if any area that you have applied it becomes wet as the product will wash away very easily.