Source: Own work


Ants are not exactly pests but when they enter the house and invade your kitchen and your cupboards looking for food or future queens take flight to swarm, they will disturb many people.

It is not necessary to eliminate an entire colony simply because they bother you, as ants are quite useful. But you can prevent them from entering the house.

To choose the best strategy, it is important to know that ants use olfactory traces. They deposit chemicals along their itinerary. This olfactory trace is then read by other ants to get to the food.

Immediate effect:

Disrupting the olfactory track will prevent other ants to follow.

To do this, locate the route and it wash with soapy water or vinegar. Lemon juice can also be used.

You should know that it will prevent other ants from entering but also prevent ants who are already inside, to get out.

But it is effective, it will prevent the entire colony to come have an all-you-can-eat in your kitchen.

It will however not prevent them from coming back the next day or next week, you will have to follow up with a more long term strategy.

Long term effect:

If an ant colony is close to your home, you can prevent them from entering by installing repulsive barriers.

Spread a trail around the door, window sill or crack in the wall:

  • charcoal powder
  • chalk: draw a line
  • pepper powder
  • chili powder (cayenne pepper kind)
  • turmeric
  • cinnamon
  • coffee grounds
  • talc
  • scouring powder

Attack the ant colony:

It is possible to decimate the entire ant colony. I personally do not like this but I will explain it anyway.

The greenest solution is based on boric acid. Well, green… I’m not sure the eradication of an entire ant colony can be called green or ecological… But it is ecological in the sense that it is not polluting.

Mix boric acid with powdered sugar and sprinkle this mixture in the vicinity ant routes.

You can also mix boric acid with condensed sugared milk and roll it into balls of 1 cm in diameter, which may be spread at strategic locations. This is also radical against cockroaches.

Boric acid is toxic and causes diarrhea and vomiting in small doses. At high doses it can be fatal. It is better not to use it if you have small children or pets.

It is found in the form of boric acid flakes at pharmacy as it is used as an antiseptic and antibacterial (for treatment of burns, cuts, sweaty feet…).

Seal openings:

As a fast and temporary solution, holes where ants enter the house may be plugged with Vaseline. It degrades over time and a more permanent repair will have to be done later.

Holes in the door or windows jambs can be filled with silicone.

For cracks, it will be necessary to repair the building.

Keep your kitchen clean:

  • do not leave dirty dishes around
  • do not leave food around
  • use airtight containers for storing your food
  • rinse recyclable containers you put in the trash: cans, PET bottles…
  • close trash cans
  • clean the cabinets and worktops with vinegar. Not only will it repulse ants, it will also disinfect the treated surfaces.

Flying ants:

If you’re anything like my mum, the swarming of future queens on a hot and dry day when you try to enjoy your patio, will not be found enjoyable.

Though I keep telling her that they do no harm, they do not bite or sting and if they enter the house, it’s by mistake, she seems to fear an invasion by killer ants.

In this case, pour water (boiling or not) down the exit hole. It will not kill many ants but they will search another exit while you continue to enjoy your sunny afternoon on your deck or patio.