The first watering of your newly installed turfgrass sod is the most important. Begin water immediately after installation of the new sod. The first water establishes how well the grass will perform for years to come.
It is critical to water new sod within a half hour after it is laid on the soil. Apply at least 1 inch of water so that the soil beneath the turf is very wet. Ideally, the soil 3 to 4 inches below the surface will be moist.
Pull back a corner of the turf and push a screwdriver into the soil. It should push easily and have moisture along the first 3 to 4 inches, or you need to apply more water. You need to water 4-5 times daily, keeping the grass wet continuously for the first 3-4 weeks. The 1/2-1 inch of soil that comes with the sod can typically only hold moisture for 2 hours before the sod is needing more moisture.
Make certain that water is getting to all areas of your new lawn. Corners and edges are easily missed by many sprinklers and can dry out faster than the center portion of your new lawn. Also, areas near buildings dry-out faster because of reflected heat and may require more water.
Runoff may occur on some soils and sloped areas before the soil is adequately moist. To conserve water and insure adequate soak-in, turn-off the water when runoff begins, wait 30-60 minutes and restart the water on the same area, repeating as needed.
For the next two weeks (or until your roots are established), keep the below-turf soil surface moist with daily waterings of approximately 1/4 inch each. Night time watering is not recommended, as there is very little water loss during those hours.
As the turf starts to knit its new roots into the soil, it will be difficult and/or harmful to pull back a corner to check beneath the turf, but you can still use a screwdriver to check moisture depth by pushing it through the turf and into the soil.
Water as early in the morning as possible to take advantage of the daily start of the grass’s normal growing cycle, and less loss of water because of high temperature evaporation.
If the temperature approaches 100 degrees, or it is windy for more than 1/2 of the day, reduce the temperature of the turf surface by lightly sprinkling the area.
During the remainder of the growing season, most lawns will do very well with a maximum total of one inch of water a week, coming either from rain or applied water. Soil conditions may dictate that the amount be applied in two settings, two to three days apart. This amount of water, properly applied, is all that is required for the health of the grass, providing it is applied evenly and saturates the underlying soil to a depth of 4 to 6 inches.