How to Prevent Ants from Invading Your Home and Yard

Ants are everywhere. While a single ant might catch your curiosity, no one wants a full-on invasion of ants, whether harmless or destructive. We reached out to ant specialists for their expertise on handling infestations. Here's how to determine the type of ant you're dealing with and how to prevent them from invading your home and yard.

Odorous House Ants vs. Carpenter Ants

"There are over 12,000 species of ants globally. Fortunately, only around 30 species typically invade our homes," explains entomologist Josh Matta. Two of the most common ants found inside homes are odorous house ants and carpenter ants.

Odorous House Ants

Odorous house ants are small (less than 1/8 inch long), and although they can be annoying, they don't cause much harm aside from contaminating sugar in your sugar bowl. You’ll spot them marching along kitchen counters or crawling up bathroom walls.

Carpenter Ants

Carpenter ants are attracted to damp wood and can cause significant damage over time. You may notice a small swarm near an exterior wall or see small holes in baseboards or windowsills. They are often confused with termites.

"Ants and termites are easy to tell apart," says Matta. "Carpenter ants have much larger front wings compared to the hind wings, which are clear, a narrow waist, and antennae that bend like an elbow. Termites, on the other hand, have wings that are similar in length and milky in color, a broad waist, and straight antennae made of many tiny segments that look like beads."

How to Eliminate Indoor Ants Without Using Chemicals

You’ll need to play detective and follow the odorous house ants to figure out where they’re entering your home and what’s drawing them inside. After identifying the infestation, here’s how to get rid of the ants and prevent them from returning.

Seal Gaps and Use Vinegar Solution

Close off any cracks or gaps and remove any food and water sources the ants are using. Mix equal parts water and distilled white vinegar to wipe away their scent trails. Vacuum up any visible ants indoors and dispose of the contents outside.

Create a Barrier

Building a barrier with substances that ants dislike can be a useful method to keep them out of your home. Sprinkling cinnamon, cornmeal, cayenne pepper, or ground chalk on door thresholds, windowsills, and baseboards forms a line that ants will avoid. However, if you have pets, make sure to research the safety of these substances before using them.

Use Citrus

Ants also dislike the scent of citrus. As an alternative to other methods, dry citrus peels and grind them into a powder using a blender or food processor. You can use peels from any citrus fruit—such as oranges, grapefruits, limes, or lemons. Then, spread the powder to create a barrier where ants are entering.

Apply Essential Oils

Essential oils can also help repel ants. Tea tree oil, peppermint, and citrus oils are all effective at keeping ants away. In a spray bottle, mix 1/4 cup of water with seven to 10 drops of essential oil, and spray it on entry points.

As a bonus, not only will you drive the ants away, but your home will have a pleasant scent. However, some essential oils can be harmful to pets, so if you have furry companions, you may want to avoid using this method.

Eliminate Moisture Sources

To get rid of carpenter ants, tackle the issue causing the damp wood they’re attracted to. Fix leaks, ensure water flows away from the house's foundation, and use fans to dry the area as quickly as possible.

How to Eliminate Indoor Ants Using Store-Bought Solutions

Before resorting to bug bombs or indiscriminate pesticide spraying, there are gentler ways to manage ants without exposing your household to harsh chemicals. Begin with tamper-proof ant bait traps placed near areas with heavy ant activity. These traps contain a small amount of food laced with pesticide that worker ants carry back to the colony to feed the queen. Once the queen dies, the colony perishes.

Professor Michael Potter advises looking for baits that include fipronil, imidacloprid, indoxacarb, thiamethoxam, or dinotefuran. For carpenter ants, Potter suggests drilling small holes into the affected areas and injecting boric acid powder using a syringe or puffer.

How to Handle Outdoor Ants

Since many carpenter ant colonies are located outdoors, trace the ant trail (they’re most active at night) and apply insecticide directly to the nest, using products such as carbaryl (Sevin), diazinon, or chlorpyrifos (Dursban).

Many outdoor ant colonies can be eliminated simply by removing their food and water sources. Small mounds can be destroyed by pouring soapy water directly onto them.

Dangerous species like fire ants, which can cause severe allergic reactions in both humans and pets, need specialized chemical baits and a structured pest management plan to target the queen and eradicate the colony.

How to Prevent Both Indoor and Outdoor Ant Infestations

The most effective way to control ants is through prevention. Since ants need food and water to survive, begin by cleaning up inside and outside your home.

• Eliminate standing water by fixing leaks in roofs and plumbing and checking crawl spaces for moisture.
• Maintain cleanliness on your floors and counters. Remove crumbs, clean up spills promptly, and avoid leaving exposed food unless it’s in a sealed container.
• Remove pet food bowls when not in use.
• Keep gutters clean and as dry as possible. Trim back vegetation around the home and keep mulch at least six inches away from the foundation.
• Seal cracks and crevices around doors, windows, and pipes with weather stripping and caulk to block ants from entering your home.