While there is no guarantee that you can solve an ant problem between the pavers of your patio or walkway, you can take steps to reduce the likelihood of an unsightly and bothersome infestation. The first line of defense is to have the pavers properly installed over crushed gravel and sand layers that have been compacted prior to paver installation. Installing pavers directly over dirt is an open invitation, not only to ants, but any number of other legged, winged and rooted pests. In addition to a quality install, using the proper joint sand acts as the final line of defense, and reduces the occurrence of ants taking up residence in your landscaping.
Choose your polymeric sand. It is available through a number of manufacturers in basic tan and gray colors. Variations in color are becoming more popular, allowing you to fully customize the look of your patio or walkway.
Turn on the local weather forecast before beginning to ensure that no rain is forecast while you will be installing the sand. Since polymeric sand is activated by water, cleaning it off a wet paver surface is a nightmare. A dry day is essential to a trouble-free install.
Pour the sand out onto the pavers' surface. Use enough that it can be swept across the tops of all the pavers and allowed to fall into the joints.
Start sweeping. Fill each joint to the top before continuing on to the next one.
Use a tamper (these can be rented from equipment rentals) to compact the pavers and the polymeric sand into the joints.
Repeat the sand application and tamping up to three times, being sure on the last application to fill every minuscule crack and crevice in between the pavers. It must be packed and solid to be effective against ants.
Clean off all traces of the sand from the tops of the pavers with a broom or blower. Get into any corners where sand might be hiding. This is essential for a good looking finished product.
Mist water over the pavers and joints with a garden hose, both to clean any remaining dust or particles away without disturbing the sand in the joints and to activate the polymeric sand. Begin at the highest point of your patio or walkway and work your way down.
Allow the sand to cure for 10 to15 minutes. The water mist activates the sand and it begins to bond and harden between the pavers. Mist again after the 10 to 15 minutes is up. Allow up to 24 hours for complete curing, though follow the manufacturer's guidelines regarding drying times.