Once your new lawn is installed, you should immediately start watering for 10 to 12 days as the roots knit to the soil. Your watering should penetrate the ground 4 to 6 inches so that a long screwdriver should easily go into the ground.
Immediately after the sod is laid, begin watering all sodded areas. Schedule watering to assure the sod is constantly wet and water penetrates the soil 4 to 6 inches. This should continue for 10 to 12 days until roots knit sod to the soil. The sod layer can easily dehydrate before roots are formed and severe damage can occur to your new lawn. Foot printing and/or the grass blades turning a blue-gray color indicate your sod is under dehydration stress and should be watered.