4 Ways to Get Rid of Ants Outside That Really Work

Ant on deck

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While it’s completely normal to see ants in the garden, they can become irksome in large numbers. Most ants are harmless and beneficial to the ecosystem. However, some species can cause painful stings, infest food, chew into wood, and damage grass with their unsightly mounds.

Whether you’ve recently had an ant invasion or just want to enjoy an ant-free lunch on your patio, read on to learn four ways to get rid of ants outside and prevent them from returning. 

From fast-acting solutions to long-lasting methods, here are four ways to get rid of ants in your outdoor space:

Tackle Nests With Outdoor Insecticide

Attacking the leader of the colony—which is the ant queen—is by far the most effective course of action if you’re able to locate the ants’ nest. Note that some species, like the carpenter ant and Argentine ant, have more than one queen so treating a single nest isn’t going to eradicate the entire colony. 

Follow the worker ants’ trails until you reach their headquarters—this is where they crawl in with food for the rest of the colony to eat. Then, drench the nest with a properly labeled insecticide and cover the area with debris to kill them off before they get a chance to relocate. 

Granules, gels, and foam ant killers are ideal for destroying nests. Gel and foam versions work best for hard-to-reach crevices (e.g. under lap siding) since they come with long extension tubes. On the other hand, we recommend granules if you’re tackling ant hills on your lawn or in your pavers. If you don’t want to go the chemical route, pour boiling water into the nests’ openings for a natural approach. Keep in mind that boiling water kills vegetation, so avoid using it on your lawn or near flower beds.

Warning

Always wear safety gloves when dealing with insecticides and follow the manufacturer’s instructions to the letter for effective results. Chemical insecticides should only be used in areas that children and pets don’t have access to unless stated otherwise. 

Use Ant Spray for Outdoor Use

Although not always preventative, ant sprays are fast-acting, which might come in handy for outdoor dining and lounging. Simply spray it wherever you see ants to kill them on the spot.

  • Aerosol sprays are great for spot treatment. Not only do they eliminate ants on contact, but they also deal with nuisance pests like roaches and ticks.
  • For a broader treatment, hose-end sprayers would be your best bet. These products hook easily to garden hoses and can be applied on foundations, patios, wooden decks, lawns, and landscapes, with some treating up to 5,000 square feet of outdoor surface. Some brands even provide ant control for up to 12 weeks and can kill the most resistant of ants. 

Not all ant sprays have harsh chemical smells. Some sprays contain only natural, plant-based ingredients, leaving pleasant scents that are enjoyable to humans and threatening to ants. Always check the back of the product to see if it’s effective against the ant species you’re trying to eliminate.

Warning

Some ant killers include synthetic insecticides (such as permethrin or cypermethrin). These chemicals can kill beneficial bugs like bees and ladybugs. They’re also highly toxic to fish and may harm birds when mixed with other toxins. Opt for sprays that use pyrethrins instead, which are lower in toxicity.

Trick the Ants With Baits

Worker ants are always on the hunt for food, so tricking them with mouth-watering treats laced with poison works like magic. Place ant bait stations along their trails or next to their nest if you’re able to track it down. They’ll then carry these “gifts'' back to their colony, poisoning the queen and all the minions that take a bite.

Ant baits—which can be store-bought or made at home—come in both liquid and solid forms. While sugar-loving ants prefer liquid baits, grease and protein-eating ants respond best to solid, crumbly baits. Again, you’ll have to first identify the ant to know which bait will work best.

This method is slow-acting, meaning it will take a few weeks to fully eradicate them all. But other than that, it offers a more permanent solution to ant problems.

Dust Their Trails With Diatomaceous Earth

Non-toxic to humans and pets, yet effective at slaying ants, Diatomaceous earth (DE) is a powdery substance made from fossilized remains of tiny aquatic algae. It feels soft to human hands, but to ants and other insects, consider DE a million little shards of glass. Plus, this powder doesn’t need to be eaten for it to be effective. A simple touch is all it takes to penetrate the ant’s exoskeleton and dehydrate it until it dies. The downside, though, is that DE doesn’t affect ants that don’t come into contact with it.

Sprinkle DE sparingly along trails, on plants they climb, and around ant mounds to kill the workers. If you manage to eliminate all foraging members, the queen will have no option but to die of starvation. Keep repeating this process every one to two weeks until you no longer see any ants.

Warning

Always wear protective gear and avoid skin contact when handling DE. While generally harmless, this powder can cause shortness of breath if inhaled in large amounts and can be irritating to the eyes and skin. Only use food-grade diatomaceous earth; pool maintenance DE is toxic to people, animals, and plants.

How To Prevent Ants From Infesting Your Outdoor Space

If you really can’t stand ants roaming around your garden or getting to your outdoor lounging and entertaining spaces, it’s best to prevent them from barging in. To prevent future ant infestations:

  • Keep your plants, trees, and shrubs free of aphids. These small, sap-sucking insects produce honeydew, which is a favorite of sweet-loving ants. 
  • Perform a broadcast ant treatment on your entire yard every few months.
  • Remove any clutter, decaying logs, leftover food, and fruit drops in your garden.
  • Use ant-repelling plants, such as mint and thyme, for further protection.
  • Store firewood and other wood piles away from areas you want ant-free. Carpenter ants often inhabit these.
FAQ
  • What kills ants outside fast?

    Whether all-natural or chemically made, ant sprays are designed to immobilize ants on the spot with the help of toxic pesticides and repelling smells. Some products even leave a residual control that continues to kill ants for a couple of days or up to several weeks.

  • When is the best time to treat outdoor ants?

    Since ants are most active at night, consider setting your ant baits a little before sundown. This way, they will be the first thing the ants notice when they leave their nest to forage for food. If you’re planning on destroying their nest, your best shot would be during the daytime when most ants are inside.

  • When should I call a pro?

    If you’re unsure of your ant type, don’t know where the nest is, or are dealing with an unusually large-scale ant issue, consider reaching out to a pest control service. A professional will have no trouble identifying the ant species and can offer an appropriate treatment tailored to your needs.