Does Cornstarch Kill Ants? How it Works

When facing an ant infestation, finding an effective and safe solution is essential. Cornstarch has emerged as a popular home remedy for dealing with these tiny invaders.  

In this blog, we’ll explore the truth behind using cornstarch a an ant killer and uncover the advantages, methods, and potential myths associated with this natural approach.  

Whether you’re dealing with indoor or outdoor ant problems, we’ve got you covered with all the information you need to make the most of cornstarch in your battle against ants. 

How to get rid of ants with cornstarch

Does Cornstarch kill Ants?

One of the most critical questions is whether cornstarch is indeed lethal to ants. The answer is a resounding yes! Cornstarch kills ants due to its unique properties. When ants ingest solid cornstarch, it forms a thick, indigestible layer in their stomachs, leading to their demise.  

does cornstarch kill ants
Cornstarch is lethal to ant

However, it’s essential to use cornstarch bait strategically to ensure it effectively targets and eliminates the ant colonies. 

Advantages of using Cornstarch to kill Ants? 

Cornstarch acts as a non-toxic alternative, making it safe for children and pets. Additionally, its simple application process and low cost make it an appealing choice for sustainable ant control solutions. 

How to kill ants using cornstarch

If you use cornstarch alone without mixing it with anything, make it a little bit wet. Ensure you clear anything that will attract the ants so they can starve. Here is how to get rid of ants using cornstarch:

  1. Put 1 cup of flour in a container
  2. Add 1/2 cup of sugar to attract the ants faster
  3. Pour 1/2 cup of water into the mixture to form a paste
  4. Spread the paste along their trail and in areas where they live

If you are dealing with a large number of ants out outside, simply spread the cornstarch over the ants. They will take this back to their colonies to feed the queen.

If the queen is no more, then it means they will not multiply and the ant population will be reduced. To make it even more effective, you can mix the cornflour with borax powder.

Cornstarch bait for ants: Mix 1 cup of cornstarch with 1/2 cup of borax and sugar, then spread it on their trail. They will carry the particles back to their nests. This is one of the fastest ways to get rid of ants because they will die in less than 30 minutes after eating the mixture.

How long does it take for cornstarch to kill ants?

Adult ants will die in less than 3 hours after taking solid cornstarch. This is because they can not eat or digest solid food. When eating any solid food, adult ants produce a juice that will convert the food into liquid before they digest it.

When using cornstarch against ants, mix it with water so that they digest it faster and easier. If you are clearing a big colony, it may take 1 day for you to start seeing some results.

Ants are always looking for food; if you want cornstarch to kill them fast, ensure that they have nothing to eat. If they eat the powder with an empty stomach, they will die in less than 3 hours.

Notes when using Cornstarch to eliminate Ants

Keep in mind these essential tips and precautions when using cornstarch as an ant killer: 

  • Keep bait away from children and pets, although cornmeal is not toxic, it can have adverse effects on the respiratory system if not used properly.
  • Remember to refresh the cornstarch bait regularly for optimal results.  
  • Exercise patience, as it may take time to see complete eradication, especially for larger ant populations.
does cornstarch kill ants
Don’t let your children and pets get close to cornstarch

What can you mix with cornstarch to kill ants?

To speed up the whole process, there are things that you can mix with cornstarch to kill ants. In most cases, you should go for toxic and sweet stuff that can work simultaneously.

You can mix cornstarch with sugar, borax, and baking soda. While borax and baking soda will kill the ants, sugar and cornstarch attract them. If you mix all those together, you shall have made one of the best homemade ant killers.

The idea here is to have the sweet stuff like sugar in low quantities and the toxic in the quantities. In this case, the baits should be equal to work best. In fact, this is one of the best and safe ways to kill those small ants in the house.

The idea here is that we are trying to kill the ants, not feed them. If you buy the baits in large quantities, you are losing the whole point. You will only be attracting the ants and keeping them away.

Does cornstarch repel or attract ants?

Cornstarch does not repel ants because it does not have any chemicals that will do so. In fact, it will attract ants because it is food, and they will eat and take some back to their nests for the rest to have a meal.

Cornstarch alone is enough to get rid of ants, and is also one of the best natural ways to kill ants. We only mix it with sweet things like sugar to make the process fast because corn will not attract the ants as fast as sugar will.

This is why in some cases, we also add borax and use cornstarch as an ant bait. An added advantage of this is that it can be used to eliminate ants indoors and outdoors.

If you have a grass plantation in your yard or compound and ants infest it, simply spread cornstarch powder all over the place and let the ants enjoy the meal. This will effectively control the population in a span of one week.

Cornstarch ants myth

One of the most common myths about ants and cornstarch is that ants can feed on cornstarch, increasing their population because they are attracted to it as a meal.

This is a myth because once they take it, it will solidify in their system, and they will die. They will take it thinking that it is a meal, but in the end, it will be deadly, and this can wipe out quite a significant number of them.

It is also a myth to say that ants cannot eat cornstarch alone because it is not sweet. Ants love cornstarch because it is made from the endosperm of corn grain. The endosperm contains natural sugar, and that is enough to attract ants because they will find it tasty.


Does Cornstarch Work for All Types of Ants? 

Understanding the effectiveness of cornstarch on various ant species is crucial. We’ll explore whether cornstarch proves equally lethal to all types of ants or if specific ant species might require alternative control methods. 

Do I Need to Keep Reapplying Cornstarch to Control Ants? 

Consistency is key when dealing with ant infestations. We’ll address the question of whether repeated applications of cornstarch are necessary for effective ant control or if a single treatment suffices. 

Can I Use Cornstarch to Kill Ants Outdoors? 

Ant invasions can extend to outdoor areas, posing unique challenges. We’ll delve into the feasibility and success rate of using cornstarch to combat ants in your yard or garden. 

What Should I Do If Cornstarch Doesn’t Seem to Work on Ants? 

In rare cases, cornstarch may not yield the desired results. We’ll provide alternative strategies and tips to enhance the effectiveness of cornstarch-based ant control or suggest other suitable methods. 

Wrapping up, remember that using cornstarch to kill ants can be an effective, eco-friendly solution. For more pest control tips using natural ingredients, explore our insightful blogs on using cinnamon, essential oils, or even orange oils to combat ants. Share the wisdom and don’t forget to spread the word about Pestweek, your go-to resource for humane and innovative pest control strategies!


  1. NCBI: Metabolism of sugars in the endosperm of developing seeds: Oxford University Press
  2. University of Florida: Insect pest traps: EDIS

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