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How Long Does Diatomaceous Earth Take To Work?

Diatomaceous Earth

Diatomaceous Earth (DE) is a chemical free, effective way to kill many different kinds of insects. Although it does not kill immediately, like some contact killers, for many people the benefits of diatomaceous earth far outweigh the wait time that is required. Diatomaceous earth is not a poison. Instead, it is the fossilized remains of a type of algae, known as diatoms. When ground up, these diatoms form a powder that has microscopic sharp edges that are not harmful to humans and other animals, but deadly to insects. These razor sharp edges cut the exoskeletons of insects, causing them to dehydrate and die. DE is often used to treat bed bugs, fleas, ants, and many more pests.

An adult bed bug crawling on skin
Content Providers(s): CDC/ Harvard University, Dr. Gary Alpert; Dr. Harold Harlan; Richard Pollack. Photo Credit: Piotr Naskrecki

How Long Does it Take Diatomaceous Earth to Work?

This process can take a few hours to a few days, depending on the insect and the conditions. An article inNational Geographic says, “Death comes in 12 hours after insects venture into diatomaceous earth. Their skins are pierced by sharp edges of the diatom’s siliceous shells, causing life’s juices to flow out.” It has since been reported that some insects die within 4 hours of contact and others may take a full day. While individual insects can be eliminated fairly quickly, a full infestation can take longer to get rid of. It is recommended that you reapply DE about once a week for a full month in order to achieve full control. This is because new eggs will hatch, and the nymphs and adult must all contact the powder in order for it to be effective. Since direct contact with diatomaceous earth is required, proper placement and application is important. A thin layer of DE can be spread in areas where insects have been known to live and travel. These areas can be indoors or outdoors and may include: behind appliances, under furniture, along baseboards, around the foundation of the home, and many other places. For hard to reach areas, a duster or puffer bottle can be used. So you may be wondering how long Diatomaceous earth will continue to be effective, the answer is indefinitely as long as it remains dry.



Although it may not be the fastest method of insect control, diatomaceous earth is chemical free, easy to use and has the added benefit that insects can not develop resistance to it since it is a mechanical means of pest control. For all of yourhome pest control needs, trust PF Harris products to get the job done right. Diatomaceous Earth works to control a long list of insects including cockroaches. Check out our products for Killing Cockroaches with Diatomaceous Earth and  How to Use Diatomaceous Earth to Control Ants