Does Diatomaceous Earth Kill Cockroaches?

dead cockroach on the floor

Got a roach problem? Meet diatomaceous earth.

This non-toxic, powdery superhero is crafted from ancient ocean critters.

It works by drying them out until they’re toast, without harming you or your pets. Just sprinkle it around hotspots like the kitchen or behind appliances.

Wondering if it really kicks cockroaches to the curb? Keep reading to find out.

Key Takeaways

  • Diatomaceous earth (DE) is made from fossilized algae and is used in pest control, food production, and filtration due to its absorbent and abrasive properties.
  • There are two main types of diatomaceous earth: food-grade, which is safe for human consumption and pest control, and filter-grade, which is used for industrial purposes and not safe to ingest.
  • DE kills cockroaches by damaging their exoskeletons and causing dehydration, making it an effective and eco-friendly alternative to chemical insecticides.
  • For optimal roach control with DE, apply it thinly and evenly in infested areas, keep it dry, and reapply regularly to maintain effectiveness.
  • If diatomaceous earth treatments fail, consider using other DIY methods like borax or professional pest control services, especially for severe infestations.


Diatomaceous earth is a versatile substance revered for its natural pest-control properties. However, it also plays a vital role in other industries, such as food production and filtration.


Diatomaceous earth (DE) is a natural pest control method targeting cockroaches‘ exoskeletons and other insects such as fleas and bed bugs.

Diatomaceous earth is highly effective against cockroaches, including common types like German and American cockroaches and their nymph stages.

Here’s how it works:

  1. Contact with DE: When cockroaches crawl over an area treated with diatomaceous earth, they come into direct contact with its abrasive particles.
  2. Exoskeleton Damage: The microscopic sharp edges of DE abrade the cockroach’s exoskeleton. This damage is critical as it compromises the structural integrity of the cockroach’s outer shell.
  3. Absorption of Lipids: Diatomaceous earth’s particles effectively absorb the lipids from the protective waxy layer covering the cockroach’s exoskeleton.
  4. Desiccation: With the protective layer compromised, the cockroach begins to dehydrate. The loss of essential fluids and lipids leads to desiccation.
  5. Resulting Death: Dehydration ultimately leads to the death of the cockroach. This process is especially effective against specific stages in the life cycle, like adult cockroaches and nymphs.


The correct application of diatomaceous earth is crucial to combat a cockroach problem. It involves a preparation phase to set up the area, followed by precise application techniques.


When prepping your space for diatomaceous earth use, follow these steps carefully to increase the effectiveness:

  1. Identify Infestation Sites: Look for areas where cockroaches congregate or travel, such as kitchens and bathrooms. Check for signs like droppings or egg cases.
  2. Clean Thoroughly: Ensure the infested areas are clean by removing human and pet food sources and spills.
  3. Remove Clutter: Ensure waste from your home is placed outside in garbage cans with locking lids until it is trash pick-up day.
  4. Seal Entry Points: Use caulk to seal cracks and crevices where cockroaches could enter living spaces. Pay attention to gaps around pipes and windows.
  5. Remove Excess Moisture: Fix leaky faucets and pipes to eliminate water sources that attract cockroaches.

Applying Diatomaceous Earth

Employ the following methods when applying diatomaceous earth to control cockroaches effectively:

  1. Choose the Right Type: Remember to pick the correct type of diatomaceous earth. Use food-grade type only to ensure your safety.
  2. Use a Duster: To ensure even distribution, apply diatomaceous earth with a duster. It helps reach into tight voids and underneath baseboards.
  3. Focus on Hotspots: Directly apply to hiding places where cockroach activity is high, such as behind appliances, crawl spaces, countertops, and inside closets.
  4. Light Application: Fine dusting is more effective than heavy layer dusting, as cockroaches will likely avoid thick piles of diatomaceous earth.
  5. Reapply After Cleaning: Clean up any diatomaceous earth that comes into contact with moisture and reapply, as its effectiveness can be diminished when wet.
  6. Check and Reapply Regularly: Check the applied areas every few weeks and add more diatomaceous earth to maintain its potency against cockroaches.

Tips to Maximize Effectiveness of Diatomaceous Earth

Several key factors must be carefully managed to maximize the effectiveness of DE for controlling cockroach populations.

Follow these steps to ensure optimal results:

Recommended ActionDetails
Assess the Level of InfestationBegin by evaluating the severity of the cockroach infestation. 
Ensure Freshness and DrynessEnsure the fresh DE is completely dry because moisture can significantly diminish its effectiveness.
Apply ConsistentlySpread DE in thin, even layers across areas, such as under sinks, along baseboards, and near entry points.
Maintain Dry ConditionsAvoid using it in humid areas or during wet conditions, and try to control the environmental moisture if possible.
Exercise PatienceContinuous monitoring and reapplication in critical areas may be necessary to achieve complete control.


Sometimes, despite your best efforts, diatomaceous earth and other DIY solutions just don’t cut it as an insect control.

If it seems like roaches have set up a permanent camp in your kitchen no matter how much diatomaceous earth you sprinkle, it’s time to pick up the phone and call in the pest control professionals!

At LaJaunie’s Pest Control, we provide tailored solutions for your cockroach issues. Here’s a brief overview of what our exterminators will do depending on your situation:

Cockroach TypeTreatment StepsCostFollow-Up
German CockroachesApply IGR to stop reproduction, and then perform the initial treatment.$280 initialMandatory two-week follow-up with an optional no-cost follow-up at four weeks.
Other SpeciesUse granular baits.StandardRegular monitoring at quarterly service.

Whether you’re in New Orleans or Baton Rouge, seeking expert help should be easy. For immediate intervention for a severe infestation, let Lajaunie’s cockroach control specialists tailor a solution that’s right for your home.

For more information about the areas we service, visit our location page.