Nothing can be more disconcerting than a line of ants tromping through your kitchen or even an entire ant colony emerging in your lawn or garden. If all you have on hand is some bleach, you might be surprised to learn that bleach can, in fact, kill and repel ants.
If you are curious about how this works and want to learn the best methods for killing house ants or repelling ant colonies using bleach, keep reading! (We’ll also cover some other methods that are much more effective than bleach!)
Does Bleach Kill Ants?
In short, yes! Bleach can kill all kinds of insects when applied directly – including ants. Surprisingly, this question has even been researched and published in a peer-reviewed journal.
However, unlike most pesticides, bleach has no residual killing effects. In other words, as soon as it is dried up the bleach will not kill anything. Bleach must be applied directly to the insect to be effective.
Bleach likely works by destroying an insect’s waxy exoskeleton, interfering with their ability to breathe, and surrounding them in a chemically hypertonic high-pH solution that disrupts the water balance in their bodies. In non-science terms, that essentially means that bleach kills insects by massively disrupting the environment their cells are used to dealing with.
So, yeah… bleach kills ants. But, it is not the most effective or the most practical way to kill ants.
Does Bleach Repel Ants or Destroy Ant Trails?
“Ant trails” describe the scented pathways that ants lay down as they walk. Ants lay different scents down as they travel to a food source and return with the food to the colony.
This helps all the other ants find the food, grab a piece, and return to the colony successfully. Since bleach is a powerful household cleaner, these scent trails are no match. Even a highly diluted bleach (such as ½ cup per gallon of water) can easily wipe away any scents that ants lay down.
While some individual scout ants travel outside the bounds of an ant scent trail, the large majority of ants in a colony are “programmed” to only follow these scent trails.
So, if you find a line of ants marching into your home, a little bleach can go a long way in preventing more from following.
Follow the trail of ants back outside with a bleach-soaked cloth in hand. Wipe across the ant trail, then mop up the rest of the trail that leads into your house. While this won’t kill a colony of ants, it should take them quite a while to find a new path into your home.
This technique will break up ant scent trails, but bleach itself may also have some repellent properties. Researchers in the study cited above claim that bleach is less repellent than Comet and Pinesol, but more repellent than Formula 409.
This should be taken with a grain of salt, as this was just one environmental study with many uncontrolled variables.
Reasons Not to Use Bleach to Kill Ants
Bleach is technically able to kill ants and may even have some repellent properties, but is it is by no means the best product on the market for killing or repelling ants. Natural products like Diatomaceous Earth (DE) for ants and chemical pesticides Raid are much more effective at killing ants quickly, and both have a residual killing effect that can last for months after the time you apply the product.
Besides the fact that bleach is only mildly effective compared to other products, there are a huge number of reasons NOT to use bleach:
- Bleach kills any plants it is sprayed on (including your lawn or houseplants!)
- Bleach can discolor many surfaces – including countertops, hardwood floors, and even concrete
- Bleach can ruin your clothes if not applied carefully
- Bleach can kill non-target organisms such as soil bacteria and worms – organisms that are beneficial to your lawn and garden
- Bleach was not made to kill ants.
Alternatives to Bleach for Killing Ants
There are a large number of alternatives that you can use to remove ants from your property, including both natural and synthetic products. Bleach might work, but all of these products will work much better!
- Diatomaceous Earth – this dust-like powder is made from the silica shells of tiny marine organisms called “diatoms.” These shells are super sharp, and they work by cutting through an insect’s exoskeleton and slowly leading to dehydration. Simply dust the path ants and using and put some dust on and around the colony and it should die off or move on in a few days.
- Essential Oils – plant essential oils contain many naturally-occurring chemicals that can kill and repel ants. For example, mint oil, peppermint oil, clove powder, and many other essential oil products have been evaluated as contact-toxins against fire ants. While you can buy some of these products directly, some companies specialize in producing natural ant repellents. EcoRaider and Wondercide are both created with a variety of essential oils for repelling many different insect species.
- Ant Baits – these products are great because they specifically target ants without unleashing toxic pesticides throughout your property and home. The best ant baits work by lacing a tasty ant-treat with a synthetic pesticide, such as spinosad or abamectin. The ants ingest the bait and the insecticide and carry it back to the colony – wiping out the entire colony in a short time. Ant baits are great for long-term ant control. Check out our Terro ant bait review.
- Ant Sprays – companies like Raid! and Ortho produce spray products that are specifically formulated for ant colonies. Some ant sprays are formulated with pesticides that work over a longer period and can be transferred throughout a colony, while other sprays are formulated to instantly kill any insect they contact nearly immediately. Be sure to pick the spray that is right for you – an ant colony emerging in your kitchen might require immediate action, while a slow trickle of ants from the outdoors can be better managed using a slow-action formula!
- Ant Granules – there are also many products on the market that package synthetic pesticides into granules that you can broadcast across your lawn. These products work in a similar way to bait-stations in that the ants will carry them back to the colony for consumption. However, these granules are much easier to use over a wider area – such as a lawn or outdoor space.