Seal Cracks in Asphalt Paving Why: Patching cracks will extend the life of your driveway by preventing water from seeping underneath, creating potholes. How: Grab a patching gun and some asphalt patching caulk, and let ’er rip! Then use a putty knife to smooth the top. When: Check your driveway for cracks every summer and plan to completely reseal it every five years (another simple process involving a bucket of sealant and a big ol’ brush).