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Borax for Ants: Does It Kill Them? (This Is How It Works)

Borax is often used to kill ants. It’s a very effective remedy if you want to get rid of the little insects. Use a mix of borax and a sugary substance for the best results.

Borax is one of the most popular boric acid products on the market. It can be found in grocery stores, hardware stores, and even some drugstores. 

5 Things You Didn't Know About Ants x
5 Things You Didn't Know About Ants

The borax will dry up any food that an ant consumes which will eventually lead to disruption of its digestive system. 

In this article, we will discuss why boric acid is lethal for ants as well as how it works against them!

What Is Borax?

boric acid

Borax is boric acid with the chemical formula H3BO3[1]. It has a white or colorless appearance and can be used to kill ants, dry out wood which makes it perfect for fire-starting kits, making slime, soap making, laundry booster, and other cool projects around your home. 

Borax also has many important uses in the medical, scientific, and manufacturing fields.

Borax vs. Boric Acid

Borax and boric acid are both natural substances. 

In fact, borax is made from boron, a naturally occurring mineral that’s found in water supplies around the world. 

Boric acid also occurs naturally but it’s more commonly manufactured through chemical reactions or extracted from minerals like borate ore. 

Boron cannot be metabolized by ants, which means borax is lethal to insects. This makes boric acid less effective as a pesticide since it can be metabolized by some types of ants.

worker ant collecting food

Does Borax Kill Ants?

Borax is lethal to ants because boric acid and borax both disrupt the digestive system of an ant [2]. The borate in borax increases pH levels within a foraging ant’s stomach, which kills it.

This also causes other ants who eat this newly killed ant to experience the same fate as the borax contained in the deceased ant is transferred to others.

This process of boric acid and borax disrupts digestion as well as causes other ants who eat this newly killed ant to experience the same fate occurs because borate ions disrupt enzyme function.

The pH level increase also affects molting which leads to borax being lethal to ants.

What Happens to Ants When They Eat Borax?

Ants are insects that eat food in the form of liquids, solids, and other foods. When borax is ingested by ants, it attaches to their stomach lining, which causes them to die from internal poisoning or dehydration caused when they lose water through evaporation.

This process happens over a period of time so borax is not immediately fatal, which means borax can be used as part of an extermination process.

How Long Does It Take for Borax to Kill Ants?

Ants start dying 24-48 hours after borax is ingested. They won’t die immediately. This gives the ants time to unknowingly spread it to their fellow ant comrades.

Ants that ingest borax will eventually release their grip on whatever surface they were standing on, as they will lose their strength.

As said, it usually takes 24-48 hours, but it can take longer depending on how much borax was ingested and the type of borax used.

If boric acid is used instead of borax, ants usually die at the same rate. This boric acid is taken back to the colony and distributed among other ants, eventually killing even more of them as they ingest borax or boric acid over time. You should start to see a reduction in the ant population within a week, at most 3-4 weeks.

Ants Have to Ingest Borax to Die

If the ants don’t ingest the borax you’ve spread out to kill them, nothing will happen. Borax is only deadly to insects if ingested. Hence, it’s important to make it enticing. This can be done with ant bait.

This borax and boric acid can cause ants to lose bodily control and become paralyzed, which leads to death by dehydration or predation (because they cannot get back home). This process usually takes longer than the boron cycle in boric acid.

carpenter ants eating

Sprinkling Borax Won’t Work

Solving the borax and ants problem requires a lot more than sprinkling borax in your house. As said, it has to be ingested, hence using some food to trick the ants will be more effective.

You can buy many types of ant baits that use this principle, tricking the ants into ingesting poison.

This is an effective way to get rid of many types of insects including cockroaches and crickets.

How Does Borax Kill Ants?

There are several ways borax can kill ants. 

When borax comes into contact with an ant, it penetrates the protective exoskeleton of the ant and absorbs water from its body.

The borax crystallizes inside of the ant, dehydrating it to death. This is extremely fast-acting for some species like fire ants, but borax can also kill slowly by poisoning an ant. 

When borax is eaten, it causes the ants’ digestive system to stop functioning.

This will make it so the ants won’t be able to get the nutrients that are essential to survival. This can take from hours to days to kill off individual ants, and weeks for borax to work its way through the whole colony.

How to Kill Ants With Borax: Step-by-Step Guide

Also read: How to get rid of ants

1. Make Borax Ant Bait

Mix borax with a sweet liquid, such as sugary water or honey. The borax mixture should be sprinkled around the ant trail and any other area ants are known to gather. This will attract them to the borax since they eat sugar.

Borax alone won’t get the ants to eat it, as it doesn’t taste good to them. It’s also odorless, which also won’t make the ants notice it.

The boron in borax works by disrupting their digestive system, which will eventually kill them. This is the same for boric acid.

ants eating foods together

2. Locate the Ants

After you’ve made your borax mixture/ant bait, it’s time to locate the ants. This is important in order to know where to place the bait.

In order to locate the ant trails, simply follow the ants! If you can locate some ants in your home or outside, follow them a little bit to find a trail of ants. This will be your best shot at getting multiple ants to eat your bait.

If you know where the ant nest is, you can also place your bait next to it. This will likely draw out the ants, making the transfer of borax from ant to nest very quick.

ant trails

3. Place the Borax Trap Near the Ant Trails

As briefly mentioned, it’s important to place the borax bait close to an ant trail (or the ant nest).

Ants use pheromones to communicate. They can let other ants know where they’ve found food. This is what makes a good borax bait effective. If you’ve made a bait that the ants find delicious, they’ll let more ants know where they found it, which will spread the borax faster.

black worker ants

4. Eliminate Other Food Sources

For borax to effectively kill ants, it should be the only food source available in and around your house. This means that you’ll want to clean up all other potential sources of sugar before setting out your borax bait.

Ants are constantly looking for food. If they can only eat your bait, it’ll make your ant-killing efforts much more effective – and it’ll make sure that you’re rid of your annoying problem faster.

ants eating food on the ground

Borax Ant Bait Recipes

You can make borax ant traps quite easily. This is a great way to get rid of ants that are invading your home without having to use an exterminator.

  1. First of all, you want to create your ant bait. If you don’t know how just follow one of our recipes in the next paragraphs.
  2. After you have created your borax mixture, you want to spread it out near an ant trail or nest.
  3. When the ants find the bait, they’ll carry it back to the nest and will (hopefully) die off eventually.

Solid Borax Ant Bait Recipe

Many borax ant bait recipes exist for ant control, but one that is very effective involves borax and peanut butter/jelly.

Just follow this simple recipe to create your bait:

  • Grab your Borax and either peanut butter or jelly – any type goes, as ants are that picky when it comes to sugar.
  • Take a tablespoon of Borax and 2 tablespoons of your topping of choice.
  • Mix the two well.
  • Place the mixture near an ant trail.

This recipe is easy to make and requires something everyone has in the kitchen: peanut butter or jelly.

Liquid Borax Ant Bait Recipe

When making a liquid borax ant bait, you can go about it two ways: with sugar or syrup.

Here’s the one with sugar:

  1. Mix borax with equal parts of white sugar. 
  2. Add the borax solution into some warm or hot water until everything has been dissolved.
  3. Pour the mix onto lids in order to make it easy to access for the ants.
  4. Place the lids near ant trails or an ant nest.

Here’s an ant bait with syrup:

  1. Take one part of borax and mix it with two parts syrup.
  2. Mix the two well until all of the borax has been incorporated into the syrup.
  3. Pour the mix onto lids to make it easy for ants to access.
  4. Place the lids near ant trails or an ant nest.

And that’s it.

Frequently Asked Questions

Is Borax the Same as Boric Acid?

No, borax and boric acid are not the same. The two both contain boron, but they’re used for different things. Both of them will kill off ants though, so you can pick the one that’s easier for you to obtain when getting rid of ants.

Will Sprinkling Borax Kill Ants?

No, sprinkling borax usually won’t kill ants. Ants aren’t attracted to raw borax, since it tastes bad and has no odor. In order for borax to kill ants, you’ll have to make ant bait first.

This is easily done by mixing it with sugar or other sugar solutions such as honey, syrup, or similar.

The boron compound found in borax acts as a stomach poison to ants and other insects, killing them in one of three ways:

  • The borax reacts with water in their digestive system, creating toxic gases that cause organ rupture or suffocation.
  • Some borate ions are absorbed into their system, causing a reaction that interferes with their metabolism.
  • Borax crystals build up in the ants’ stomachs and create blockages as boric acid crystallizes out of solution within them. These actions make borax effective against ants because it acts from the inside to break down an ant’s exoskeleton tissues and dehydrate them.

Will Borax Kill the Ant Queen?

Yes, borax will kill the ant queen just as any other ant. The difficult part is getting the borax to the ant queen, as she doesn’t come out of the nest. She will be packed away in the nest, while workers bring her food and care for her.

The borax powder is effective against ants because it works as an irritant. The boric acid prevents the stomach enzymes of the ant from working properly, which makes them die within a few days after ingesting boric acid.

About Teodoro Pittman

Teodoro is a nature and animal lover. He specifically focuses on insects, such as ants, bees, and the like. In his free time, he takes care of his own ant farm, where he analyzes their behavior. Teodoro has spent the last 7 years studying the intricate behavior of these small creatures.