The presence of ant colonies in outdoor hardscaping is a common problem for many homeowners. These insects can quickly undermine the integrity of a patio, driveway, or walkway, leading to visible mounds and structural issues. Dealing with an infestation does not require harsh chemicals that can harm the surrounding environment, children, or pets. This guide provides effective, entirely natural strategies focused on safe, practical solutions to eliminate current colonies and prevent future nesting in your pavers.
Why Ants Choose Paver Joints for Nesting
Ants are drawn to the spaces between pavers because the joint sand and underlying base material create an ideal, sheltered habitat. The granular materials offer stability, excellent drainage, and protection from weather and predators. This structure provides a consistently warm, dry environment perfect for the queen to lay eggs and for the colony to expand its tunnels.
The core issue arises when ants actively excavate the joint sand and the finer particles of the bedding layer to construct their subterranean galleries. This tunneling activity causes the displaced material to appear as small mounds on the paver surface. When enough of this foundational material is removed, the paver units lose their base support, eventually leading to uneven surfaces, movement, and sinkage.
Natural Methods for Immediate Colony Disruption
For an active nest, immediate action is necessary to eliminate the colony at its source. A direct and effective method is the application of boiling water, which quickly kills ants, larvae, and the queen upon contact. Pour near-boiling water directly into the main nest opening, ensuring a slow, steady flow so the heat can penetrate deep into the tunnels. This method should be used with caution to prevent accidental burns or damage to surrounding plant life.
Alternatively, a dish soap and oil solution can be sprayed directly onto the ants and their trails. Dish soap contains surfactants that break down the ant’s waxy, protective exoskeleton, leading to suffocation and dehydration. Combine liquid dish soap with vegetable oil in a spray bottle filled with water to create a potent, non-toxic contact killer.
For a slow-acting approach that targets the entire colony, a simple food-grade bait can be deployed. Ants are attracted to sweet substances, so a mixture of cornmeal or raw cream of wheat with sugar can be placed near the nest entrance. Worker ants carry this material back to the nest, where the indigestible food substance disrupts the colony’s digestive processes, leading to colony decline over time.
Creating Natural Barriers and Prevention
Once the immediate infestation is addressed, establishing a long-term, natural barrier is necessary to prevent re-infestation. Diatomaceous Earth (DE) is a highly effective, mechanical deterrent made from the fossilized remains of microscopic aquatic organisms. This fine powder works by scratching the ant’s exoskeleton, causing it to dehydrate and die.
Use only food-grade DE, not the pool-grade variety, and brush a light, even layer into the paver joints. The powder must remain dry to be effective, requiring reapplication after rain or heavy watering.
For a liquid repellent, an application of white vinegar mixed with an equal part of water can be sprayed along the edges of the patio. The strong scent disrupts the pheromone trails ants use for navigation. Specific essential oils, such as peppermint, cinnamon, or clove oil, can also be diluted with water and sprayed, serving as a powerful sensory deterrent.
The final and most structural step in long-term prevention is ensuring the paver joints are completely filled and sealed. After eradication, replace any lost joint sand with fresh material or, ideally, polymeric sand. Polymeric sand solidifies when activated with water, creating a hardened, physical barrier that ants cannot easily tunnel through. This is the most effective way to maintain stability and block future entry points.