With the return of warmer weather, it's not uncommon to see ants reappear in our homes, businesses, or buildings. In the spring, these insects awaken and go in search of food, often inviting themselves inside our homes. Rather than immediately calling a professional exterminator, it's entirely possible to treat an ant infestation yourself effectively and economically. In this article, we explain why ants appear in the spring, which species are the most common in Canada (including the dreaded carpenter ants), why rapid action is essential, and how to use liquid and gel baits —particularly the GreenWay and Terro products available on the L'Exterminateur en Ligne website —to eliminate the colony at the source. Finally, we'll see what additional accessories can optimize the treatment and what actions can be taken to prevent the return of these unwanted pests.
Why do ants appear in spring?
As soon as the outside temperatures warm up, ants emerge from their winter dormancy (diapause) and resume their activities. They need food and water again , and will naturally explore the surrounding area in search of these resources. Our homes then become very attractive, as they offer abundant warmth and food. The first ants observed are often scouts : if they find crumbs in your kitchen or spilled sugary liquid, they will return to the nest, leaving a scent trail to guide their fellow ants to this source. This is how a handful of ants can quickly turn into a veritable colony invading your floor or cupboards.
In early spring, it can also be common to see large black ants appear in the house—often carpenter ants—sometimes even when there is still snow on the ground outside. This is because some colonies have been able to establish themselves near the foundations or inside the structure itself, allowing them to become active very early in the season. Conversely, if you only observe ants from May-June, these are probably colonies located outside that occasionally send workers inside to look for food. In any case, spring is the critical period when you must be extra vigilant, because the presence of ants at this time of year can indicate the beginning of a serious infestation if no action is taken.
The most common types of ants in Canada
An adult carpenter ant (Camponotus). These large ants can burrow into wood to build their nests, causing structural damage to buildings.
Several species of ants can infest buildings in Canada. The most common are the carpenter ant , the little black ant , the odorous ant (Tapinoma, which gives off a yeasty odor when crushed), the robber ant , and the pharaoh ant . The pavement ant (Tetramorium) is also widespread and can become a pest when it colonizes lawns and infiltrates homes.
Among these species, carpenter ants ( Camponotus spp. ) are particularly feared. Larger than the others (workers can measure up to 12–13 mm), they damage the structure of homes by digging galleries in the wood to establish their colony. Unlike termites, they do not eat wood but move it, producing visible sawdust near infested areas. The danger is that a well-established carpenter ant colony can weaken frames and structures over time. In addition, these ants often form satellite nests : even if the main colony is outside, they can create a secondary nest in your walls or attic, especially if damp wood is present. Tenacious , they return every year if they are not completely eliminated – their colony can grow from year to year if left unchecked. Pharaoh ants, on the other hand, are very small yellowish ants (2 mm) that live inside heated buildings; they form huge multi-nest colonies and require a specific approach (usually also using baits). Whether it is carpenter ants or smaller species, it is important to correctly identify the type of ant to adapt the treatment, but in all cases the basic control techniques remain similar.
The importance of acting quickly
Seeing a few ants wandering around your home in the spring shouldn't be taken lightly. It means a colony has found something useful in your environment (food available, shelter, etc.), and it could establish itself permanently if nothing is done. Acting quickly is essential to prevent them from becoming established permanently . By treating at the first signs, you can eliminate the colony while it's still small, before it grows large and gets out of control.
An ant infestation can escalate quickly: every day, the workers bring food back to the nest, allowing the queen to lay more eggs and the colony to grow. The longer you wait, the more numerous and difficult to remove the ants will be. Furthermore, some species, such as pharaoh ants or Argentine ants, can split their colony in the event of danger (inappropriate insecticide spray, nest disturbance), giving rise to several separate colonies—a phenomenon known as the "swarming effect," which further complicates the problem. Early, targeted, and appropriate action can prevent this from happening.
Finally, in the case of carpenter ants, taking immediate action can limit material damage. If you notice the presence of winged ants inside (a sign that a mature colony is swarming) or small piles of sawdust, there's a good chance that a carpenter ant nest has been set up in your home. You must then treat immediately to prevent these wood-eating insects from continuing to weaken the structure of the building.
Why choose liquid baits over immediate-effect insecticides?
Terro ready-to-use liquid bait station: simply cut or detach the lid to activate it, and the ants will come and feed on it themselves.
When trying to eliminate ants, it can be tempting to use conventional insecticide sprays or powders that instantly kill visible ants. However, these instant-effect products only attack the tip of the iceberg: the few ants you see. The vast majority of the colony (the queen, larvae, and many workers) are hiding in the nest, safe and sound. Killing ants as they wander around won't eliminate the problem—worse, it can worsen the infestation. If an insecticide acts too quickly, the affected ants die instantly, and the rest of the colony will avoid the treated area, rendering the treatment ineffective . You then risk creating a dispersion of the ants' path without reaching the heart of the nest.
Insecticidal baits ( in the form of poisoned sweet gels or liquids) are by far the most effective method for eradicating an entire colony of ants. The principle of a bait is to offer the ants food that they find irresistible, mixed with a slow-release toxic active ingredient. The worker ants will be attracted en masse by the bait, will consume it and, above all, will carry some of it in their stomachs to the nest to feed the other members of the colony (larvae, other workers, queen) . The insecticide (often borax or a compound from the borate family in domestic baits) does not act immediately on the individual: it disrupts its metabolism a few hours later, which gives the worker time to make several round trips and share the poisoned food with the entire colony, and especially, the queen . Only in this way can you eliminate not only the ants you see, but also all those you don't see (hidden in the walls, under the floor or outside).
Conversely, if you spray a product that kills the ants immediately, the workers die before they can return to the nest. The queen, who lays the eggs, remains unharmed and will continue to produce them; very quickly, new ants will replace those you have eliminated. In addition, the sudden disappearance of a few ants can alert the colony: they may change their path or move the nest to protect themselves, further complicating the task. This is why experts almost always recommend using bait first for ants, especially for difficult species like carpenter or pharaoh ants.
Liquid baits therefore offer better long-term performance , even if they require a little patience. Among the most effective baits on the Canadian market are GreenWay and Terro , available on the website L'Exterminateur en Ligne . These two products work according to the principle described above. For example, GreenWay liquid bait incorporates boron into a food base that is very attractive to ants (including carpenter ants). Worker ants bring this bait back to the nest to feed the larvae and the queen , the toxic effect manifesting itself with a slight delay, which ends up destroying the entire colony . For its part, Terro ant bait uses 5.4% borax (sodium tetraborate) in a sugary liquid. Terro generally comes in the form of pre-filled stations ready to use, which avoids coming into direct contact with the product. These are two proven solutions that, when used properly, allow you to achieve results comparable to professional treatment at home while spending much less.
How to properly apply GreenWay and Terro for optimal eradication
Using ant bait requires some precautions and know-how to get the most out of it. Here's a step-by-step guide to maximize the effectiveness of your treatment:
-
Place baits in the right places: Identify the paths taken by ants (baseboards, floor corners, behind counters, under the sink, etc.) and the areas where they are particularly active. Place the Terro liquid bait stations directly on the ant paths or in the immediate vicinity of suspected anthills. For GreenWay (which comes in gel form in a syringe), place small drops of bait on these transit areas – ideally in small dedicated bait stations if possible, to avoid drying out and any accidental contact. Don't hesitate to place several bait stations : for example, use the 6 Terro stations provided in the box to provide enough bait for the entire colony. Outdoors, you can also install stations around the house (patio, foundation) to intercept the ants before they enter.
-
Remove competing food sources: Before and during treatment, ensure that no other accessible food will distract the ants. Thoroughly clean up crumbs, store food in airtight containers, and do not leave dirty dishes or open trash cans lying around. This will ensure that the ants are not tempted to eat anything other than the toxic bait that has been placed. The more the bait is their only recourse, the more they will consume it, and the faster the colony will become contaminated.
-
Do not use insecticides or household products nearby: Absolutely avoid spraying insect repellent, air freshener, bleach, or any other chemical near bait stations. Even a simple swipe of multi-surface cleaner around the bait can contaminate it and repel ants , ruining your efforts. Likewise, do not use ultrasonic devices or repellents in the same room during treatment. Instead, the ants need to feel confident enough to come and feed on the bait.
-
Let the ants consume the bait freely: Once the bait is in place, do not disturb the ants that are gathering around it. It is often surprising (and a little disgusting) to see dozens of ants rushing for a drop of bait, but it is a good sign! It is normal to see more ants in the first few days , as the bait attracts many individuals. Resist the temptation to kill them outright: let them go back and forth, as each one that returns to the nest contributes to poisoning the queen and her sisters. Also, do not wipe up the bait or the surrounding soil while the activity is ongoing.
-
Keep the bait available over time: bait treatment is not instantaneous; it takes a few days to a few weeks. Leave the stations in place as long as necessary , until you no longer see any ants. Manufacturers recommend ensuring continuous bait availability for at least 14 days to eliminate a large colony. Monitor the condition of the stations: if the liquid bait is completely consumed or has dried out, replace it with a new station (or add fresh product to the gel station). Reposition the bait if necessary if the ants have changed their path. Repeating the bait placement over several weeks ensures that all successive generations of ants are eliminated until no more appear.
By following these steps, you should notice a drastic reduction in activity after a few days: fewer and fewer worker ants roaming around, then none at all. A treatment is considered effective when several consecutive days pass without any visible ants. You can then remove the baits and move on to the prevention phase. If ants persist after 2 to 3 weeks, it may be either another separate colony that has taken over (in which case, continue baiting a little longer), or a very large inaccessible nest (for example, a nest of carpenter ants in the structure) requiring professional help.
Additional accessories to maximize treatment effectiveness
To optimize your fight against ants, L'Exterminateur en Ligne offers various useful accessories in addition to baits. Among these, refillable bait stations are particularly practical. For example, the Bug Bar® bait station is a small, ingenious, safe and easy-to-use plastic box , designed to hold a gel bait like GreenWay. This station allows you to deposit the poison in a targeted manner (for example, under a refrigerator or along a baseboard) while preventing the bait from drying out or leaking. It has a lid with an opening that allows it to be refilled even when it is closed , which avoids having to reopen it once the ants have become accustomed to coming to eat there. By using this type of station, you also protect the bait from dust and prevent pets or children from accidentally touching it.
If your ant problem extends to the outdoors (eg, anthills in the garden, ants entering through the deck), you may want to consider outdoor bait stations . For example, there are Ants-no-More stakes ( which allow you to apply bait like Greenway directly indoors) that are simply driven into the ground around the house. These are designed to withstand harsh weather conditions. Placed strategically (along foundations, near nests in the lawn, around aphid-prone trees that attract ants), these baited stakes eliminate ants before they can enter and can greatly reduce infestation pressure. Just be sure to follow the manufacturer's instructions for installation.
Finally, to make things easier for you, L'Exterminateur en Ligne also offers complete treatment kits containing everything you need to combat ants. These professional "ready-to-use" kits generally include bait (liquid or gel), application stations, detailed instructions, and other useful tools. This is the easiest way to solve your problem , as everything is already included in a coherent package. By opting for a kit, you are sure to use products that complement each other effectively and you save money by not buying a multitude of products separately. These kits are designed to provide a professional solution at your fingertips , without waste or excess.
Tips to prevent ants from returning
Once the infestation is eliminated, it would be a shame to see a new colony take over a few weeks later. Here are some preventative measures to adopt to prevent ants from returning to colonize your spaces:
-
Maintain strict cleanliness: Ants are strongly attracted to sugary foods and leftover food. Be sure to promptly clean up any sugary substances (juice, honey, soda, etc.) spilled on counters. Regularly sweep or vacuum the floor to remove crumbs. Eliminate all potential sources of food and water : store food in airtight containers, empty and clean the trash frequently, and don't leave standing water in the sink. The fewer incentives your home offers, the fewer reasons ants will have to enter.
-
Seal entry points: Inspect the exterior of your property and seal off as many ant entry routes as possible. This includes cracks in the foundation and masonry, gaps around pipes and conduits, poorly fitted door and window frames, or poorly sealed vents. A little caulking or expanding foam can go a long way in blocking ant access . Also consider screened windows and tight door bottoms. Closing off these ant "highways" greatly reduces the risk of an indoor ant invasion.
-
Eliminate odorous trails: When ants have traveled over a surface, they leave trail pheromones to guide their fellow ants to the food source. After successfully treating an area (eradicating the infestation), clean it with detergent or diluted white vinegar to remove these chemical traces. Pay particular attention to countertops, baseboards, and other areas where you have seen ants moving. This will prevent a new scout ant from stumbling across an existing trail in the future and starting the process again.
-
Monitor the area around your home: Outside, manage factors that favor ants. Move piles of firewood, stumps, or stored planks away from the house (carpenter ants love damp, rotting wood). Prune tree or shrub branches that directly touch the roof or walls: these are natural bridges for ants and other insects. Control aphid colonies on your plants, as they secrete honeydew, which ants love. If you spot a nascent anthill near your house (a small cone of fine soil emerging from a crack in the sidewalk, for example), destroy it mechanically or treat it locally before it thrives.
-
Be careful when bringing objects into your home: some infestations begin with the inadvertent introduction of a fertilized queen or workers via a contaminated object. For example, a potted plant that has been outside may harbor ants in its soil, as may old salvaged furniture or cardboard boxes that have been in a garage. Inspect and, if necessary, treat these objects preventively (a light dusting of diatomaceous earth if necessary) before bringing them indoors.
By following these tips, you'll drastically reduce the chances of new ants invading your home. Prevention is your best friend: a clean, intrusion-proof, and ant-unfriendly home will be much less likely to be invaded again.
Conclusion
Ants are an integral part of our ecosystems, and their presence in the spring is a natural phenomenon. However, when they venture inside our homes, they can quickly become a headache . Fortunately, by understanding why and how they operate, we can arm ourselves with the right strategies to get rid of them effectively. Treating an ant infestation yourself in the spring is entirely possible , provided you act quickly and use the right tools. By favoring liquid and gel baits like GreenWay and Terro – which target the colony at its source – and by equipping yourself with suitable accessories (bait stations, etc.), you can overcome the most stubborn anthills without breaking the bank. The professional-quality products available on L'Exterminateur en Ligne offer individuals the means for effective pest control while remaining simple to use.
Let's not forget that successful treatment goes hand in hand with long-term preventative measures. By maintaining a healthy environment and physically preventing ants from entering, you'll ensure long-term peace of mind. This way, you'll be able to fully enjoy the return of spring without these unwanted guests, at a cost of modest effort compared to the benefits. If you're unsure or your infestation is getting out of control, don't hesitate to call a professional for a diagnosis—but in the vast majority of cases, by following the advice in this article, you'll be able to eradicate the ants from your home yourself and prevent them from returning anytime soon. Happy ant hunting and happy spring to all!
Note :
Here is an approximate estimate of the quantities of product needed based on the surface area of 1000 square feet.
Greenway
For moderate infestation: 2 syringes per floor
For heavy infestation: 3 syringes per floor
Terro (liquid bait) :
For moderate infestation: 1 1/2 packets per floor
For heavy infestation: 2-3 packs per floor