First published April 2008, last updated March 2013

I love to watch ants go about their business. They perform an important role in the environment – cleaning up dead insects and animals, transporting seeds and aerating the soil. They aren’t so interesting when they infest our houses though!

Usually we reach for insecticide when ants become a problem; but there are more environmentally friendly ways of deterring ants that don’t necessarily have to involve killing.

After a question from a reader about this, I dug back through the articles I had already published and found a few tips, but I also put the question to readers of my newsletter – and received a stack of great tried and tested ideas! I’d like to thank the following readers who contributed:

Cheryl, Elizabeth, Christine, Debbie D., Bonnie G, Becky K. Susan G., Stephanie H., Charlotte, Kathern T., Dan L., Jess A., Melissa B. and Kel.

Ant deterrent tips

Here’s some things you may want to try before reaching for that can of insecticide, depending on the application:

• Pouring lemon juice around areas ants frequent.
• Sprinkle cinnamon or place in cheesecloth bags in affected areas. Cinnamon was a very popular choice with quite a few readers reporting it being highly effective.
• Baking soda can deter ants – pour a solid line in areas of activity and they won’t cross it.
• A ring of coffee grounds around sensitive plants can discourage ants.
• A puree blend of orange peel and water can be applied to an area to discourage ants from crossing.
• Ants hate vinegar; so spray it around doorways and other areas they frequent to repel them. A small container of vinegar mixed with honey placed in affected areas appears to do the trick too.
• A reader reported baby powder stopped them dead in their tracks.
• Pouring boiling water over their tracks (destroys the scent trail)
• Sprinkling a circle of ground cloves around pet food bowls
• Removing rocks and wood from around the garden
• Planting mint around vegetable patches, flower beds and around the house
• Quite a few readers found cinnamon sprinkled across ant scent trails to be very effective
• Citrus oil is a good deterrent; it can soaked into a piece of string and place around scent trails.
• Use a piece of chalk to draw a line over trails – again, the ants won’t cross it. Chalk also has the advantage of being able to be used on vertical surfaces

Brenda W. also contributed this tip:

“Pour a small bottle of peppermint oil into a pump spray bottle, put a few drops of dishwashing liquid into small bottle and top up with cold water, recap it and give it a couple of shakes. Pour this into spray bottle and top up spray bottle with water. I spray my bench with this and I don’t get ants anymore and you get a lovely fresh smell in the kitchen.”

Another enterprising reader decided to work with the ants rather than against them. She made a sugar trail away from the house to her compost pile and put out the intent that they would find a greater feast there. It worked!

Ants invade for a reason – usually for food or water, so be sure to keep food items well secured and clean up after you prepare food. Also check plumbing for leaks, particularly under sinks. Dead insects can attract large numbers of ants, so check window sills and other areas where they may accumulate.

Ant eradication tips

Unfortunately, some times you’ll need to eradicate the ants rather than deter them. A couple of greener ways to do it (but unfortunately not very kind to the ants):

A mixture of 1/8 teaspoon of powdered borax and sugar or honey will attract and kill ants. This is a mixture that is often used in commercial ant-specific products. Worker ants take it back to the nest and pass it onto other ants, killing the colony. While borax in small quantities is relatively harmless to larger animals, in big enough doses it can kill, so be cautious about placement and keep out of reach of pets and children.

A reader reported using dry grits to kill ants; a non-toxic strategy she’s used with success for 20 years. The theory behind it is that the ants eat the grits and when they drink water the grits expand in their stomachs, killing them.

Hopefully one of the above tips will help you in your environmentally friendly control of ants! If you have any other tips, please add them below.