Will diatomaceous earth kill ants?

Updated on July 2nd, 2024

The dark, overcast and menacing sky threatened to send me home. The sea—rough and turbulent—whipped my small boat around as if it were a child’s toy. Like a mother reprimanding her child, the wind howled violently around me, telling me that I shouldn’t be here. Frost clung to my stubble. Clad in a wool hat pulled down low over my ears and anorak jacket zipped tightly to my chin, my frame was well- concealed. I was lobster fishing 20 miles off the shore of Portland, Maine. Three hours after setting my traps, I hoisted the ropes and lifted the rectangular frames into my creaky boat, securing four lobsters—enough for the day, 

That evening, as I prepared the lobsters for a candle-lit feast, I was thankful for the blazing fire that warmed my frame. Hearing the crackle of their exoskeletons as they revealed the white, tender meat hidden under their tough frames, I thought of the exoskeletons of ants.

>>> Eliminate ants with the world's most effective eco-insecticide

How strong are ants?

Ants, the number one pest in the United States, have super-strength and are able to carry up to 20 times their body weight. If either of us were a super-ant—meaning that we could carry above and beyond the average of 10 times our body weight— that would mean that you could easily lift a sport utility vehicle or a white rhino (which weigh approximately 4,000 pounds).

Ants are extremely strong because:

• They don’t have bones. 
• They have exoskeletons that help distribute any weight they’re carrying. 
• They have exceptionally strong muscles in their jaws.
• They are small. Typically, the smaller an insect (or animal) is, the stronger it is in relation to its size.

While ants are renowned for their remarkable strength, this very trait makes them formidable pests—often necessitating effective control strategies. One such method is the use of diatomaceous earth, a substance that leverages a physical rather than chemical mechanism to manage these resilient insects.

Will diatomaceous earth kill ants?

In addition to the effectiveness of diatomaceous earth (DE) against wasps, cockroaches, moths and many other flying insects, DE will kill ants—including carpenter and fire ants.

DE is made up of the fossilized remains of tiny aquatic organisms called diatoms. These diatoms have sharp, pointed, knife-like surfaces that scrape an ant’s razor-thin exoskeleton and stick to it like burrs as it walks through the powder. This scratching, scraping and sticking cuts through the ant’s cuticle, removing oils and fats from its exoskeleton—its defense and protection—and causing the ant to dry out and die from dehydration.

For this to happen, all an ant has to do is walk through the seemingly powerless powder. An ant will willingly do such, as the DE seems to pose no threat. As the ant marches its way across, the tiny dust particles (of the DE) cling to its legs and its body. Now, its death is imminent. It is only a matter of time.

Tip: Dr. Killigan's Dust to Dust Plant-Powered Insect Powder is a safer and more effective alternative to DE for insect control, with proven kill times up to 50% faster. The advanced formula—utilizing essential-oil nanotechnology and fine silica particles—penetrates the waxy outer layer of insects and attacks their nervous systems.

In tests with fire ants, Dust to Dust demonstrated an average kill time of just 5.3 hours, compared to 9.1 hours with DE. Studies have also shown that the addition of essential oils to the silica significantly boosts the powder’s potency, enabling it to kill insects up to 70% faster than traditional DE.

Can ants develop resistance against poison?

Ants can develop resistance against poison, but they cannot develop resistance against DE, as DE—as already mentioned—does not kill through a chemical process. It kills through a physical process.

In addition, DE is a naturally occurring substance—primarily composed of silica— which is found in sedimentary rock (in the earth’s crust). Silica—a mineral in nature—is a component of everything from sand and rocks to plants and humans.

It’s important to note that ants can build up a resistance to any poisons or any chemicals that you may have used in the past. This is because they are able to develop systems to survive the poison. Their immunity to the poisons depends on:

• The toxicity and combination of the pesticide(s)
• An ant’s genetic and physiological structure
• Other environmental factors that help ants evade death from future poisoning

How fast does diatomaceous earth work on ants?

Because ants have very small exoskeletons, kill time should occur within a 24-hour timeframe. It depends on how much powder the insect interacts with. 

If an insect walks through the powder and only gets it on its legs, kill time can take anywhere from 24-48 hours. If the insect gets a fair amount on its whole body, kill time is much less, typically 8-10 hours. In general, DE takes about 16 hours to kill red ants and 24 hours to kill black ants (as they’re a little hardier).

Additionally, when ants attempt to clean the powder off their bodies, they may ingest it, accelerating the dehydration process and potentially shortening the kill time further.

Is diatomaceous earth safe?

According to the Food and Drug Administration, DE is GRAS, or "Generally Recognized as Safe." In fact, DE is an ingredient in many brands of toothpaste, has been used as an anti-caking agent and can be beneficial for treating high cholesterol and improving the health of skin and teeth—among other things. The food-grade form of DE is purified, amorphous (not crystalline), chemically inactive (inert) and harmless.

DE can safely be used around your pets and children. However, one word of caution is necessary: when spreading DE, it’s important not to inhale the dust particles, as they can irritate the respiratory tract. Once the dust settles and is no longer airborne, the area is safe for normal activities. To prevent inhalation during application, consider wearing a dust mask, especially in enclosed spaces or when using large quantities.

Note: Dust to Dust meets the criteria for a 'minimum-risk' pest product under U.S. law, as its ingredients have been determined to 'pose little to no risk to human health and the environment.' This highlights its suitability for households seeking non-toxic, environmentally friendly pest control options.

How do you use diatomaceous earth on ants?

There are many uses for DE. Here are simple, easy-to-follow instructions on how to best apply DE for effective ant control:

1. Identity location. Identify where you’re wanting to eradicate the ants, whether this be a trail across your kitchen wall, a mound in your backyard or a path that crosses your sidewalk lined with petunias. You may also use it as a preventative measure and apply it around the perimeter of your backyard.
   
   
   
   
2. Prepare the Insect Buster. Using the provided funnel, fill the bulb duster three-fourths full of food-grade DE and shake it. The steel ball—already in the cylinder—will break up any powder clumps.
   
   
3. Apply a thin coating. By applying pressure to the bulb duster, disperse the DE where you’ve seen ant activity.
   
   
4. Hit ants' entry points. Using the extension rod, spray inside cracks, outlets and gaps around wiring.
   
   
5. Target additional entry points. Apply DE along your baseboards, the perimeter of your kitchen floor and on window sills.
   
   
6. Use the Insect Buster’s extension rod. If you’re encircling your home (or yard) with our top-of-the-line protection, use the shake and squeeze method as you walk, going out six to twelve inches from your home’s foundation. Be sure to include the area under your porch. Due to crawl space, applying the powder under your porch may be difficult. In this instance, use the extension rod to spray as far into this space as you are able.
   
   
7. If using outdoors, spread well. Apply DE close to the ground, avoid plants and flowers that don’t need the protection (so as not to harm the bees), and choose a non-windy day. DE can be spread in the mulch, garden soil and grass around the perimeter of your house.
   
   
8. Repeat (outdoors) and relax. Keep an eye on the places you’ve treated. The powder will need to be reapplied after heavy rain and periods of high humidity, depending on the conditions and the size of the insect infestation you’re fighting.  
   
   
   
   
9. Repeat (indoors) and relax. As I’ve mentioned, DE will kill all ants that walk through it. Ants, however, will not bring this powder back to their nests, as they do not see it as food (unlike poisoned, toxic and harmful ant bait). Therefore, you may need several applications, as ants can be sneaky and may create alternative paths into your home.
   
   
10. Sweep or vacuum. In terms of safety, there is no need to immediately remove the DE. DE is non-toxic and—as long as it remains—will continue to be active. If your ant infestation was severe, consider leaving it in place for one to two week’s time. Once ready to clean up indoors, sweep up the powder or use a vacuum with a HEPA filter. (The DE powder will burn up the motor of a regular vacuum).
    
    
11. Remove lingering pheromones. Apply Six Feet Under Plant-Powered Insect Spray where trails of ants once were. This will serve to remove any pheromones that were left behind by the ants.