Does Diatomaceous Earth Kill Ants?

If unsightly ant mounds are popping up in your garden, you’ll want to take action to get rid of them.

If you’re looking for a gentler pest control agent, diatomaceous earth is a popular option. We’ve shared the use of diatomaceous earth for aphids – but does diatomaceous earth kill ants?

Using Diatomaceous Earth for Ant ControlPin

Unfortunately, this organic agent isn’t effective against all species of ant. We will discuss how and when to use diatomaceous earth to kill ants and what other tactics you can try with it.

What Are Ants?

“Ant” is a broad term that describes over 10,000 different insect species belonging to the Formicidae family. These social insects live in ant colonies and exist almost everywhere globally, and they thrive in hotter climates.

Depending on the species, ants can range from less than half an inch to over one inch long. Colors include black, brown, red, or yellow.

Individual ants can be tough to spot outside among plants. Most homeowners discover them after spotting an anthill.

Unfortunately, destroying an anthill won’t do much besides enrage the colony occupants. The colonies can number in the thousands, living underground in a system of tunnels and caves.

What Damage Do Ants Cause?

Ants can cause damage both directly and indirectly, depending on what type you’re dealing with.

Colonies that build their nests near plants can disrupt the plant’s root system. They can also bury plants while they dig out dirt to create their underground tunnels.

Ants also “farm” other pests like Aphids to feed off the honeydew. More on Ants Farming Aphids.

The majority of ants are carnivores and won’t eat through your plants like herbivores such as caterpillars.

But, there are exceptions to the rule. For instance, leaf-cutter ants remove pieces of leaves to take back to their colonies to grow a fungus they then eat.

If you have fire ants, you also risk another sort of damage – unpleasant bites or stings if you get too close.

What Is Diatomaceous Earth?

Diatomaceous earth is a naturally occurring, crumbly, sand-like deposit. It’s the product of fossilized organisms, and the primary compound in it is silica.

These microscopic, sharp silica shards can cut through an insect’s body. Diatomaceous earth also dries out insects by absorbing fats and oils from their exoskeletons.

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The food-grade version is non-toxic and natural, making it safe if you have kids or pets. Beware: the industrial variety is toxic and can be dangerous.

How To Use Diatomaceous Earth for Ant Control

First, wear a dust mask before handling your food-grade diatomaceous earth. It might not be toxic, but it can still irritate your sinuses if you inhale it.

Avoid watering your plants before you begin. This natural insecticide works best under dry conditions.

Sprinkle large amounts of the earth on and around the anthill to ensure that the ants will have to walk through it.

Unlike chemical pesticides, diatomaceous earth doesn’t work immediately. It can take up to 24 hours or longer.

The exact length of time it will take to kill the ants depends on the species, how much you use, and whether it remains undisturbed and dry.

So, does diatomaceous earth kill ants? The results vary.

It has little impact on leaf-cutter ants. Yet it can work against fire ants used with other insecticides such as pyrethrins.

Remember that diatomaceous earth must be dry to be effective. If you live in a wet or humid region, you might have to resort to other methods of pest control.

Integrated Pest Management Program (IPM)

You’ll have a better chance of solving your ant problem if you try a multifaceted approach. That includes common-sense practices such as:

  • Watch and identify

Figure out how widespread the ant infestation is and what species you’re dealing with. A single anthill on the outskirts of your garden isn’t as much a concern as one underneath your prize roses.

  • Control

Try out several methods at once for a higher chance of eliminating these unwanted pests.

  • Prevention

Sprinkle diatomaceous earth and other organic or chemical deterrents around your plants.  Try cayenne pepper, cinnamon, or borax.


So, does diatomaceous earth kill ants?

Yes, it can be a strong deterrent – but not all ants will respond to it the same way.

An Integrated Pest Management (IPM) program is the ideal strategy to get your garden ant-free and keep it that way.

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