A new sod lawn requires special care to ensure it takes root and thrives in its new space. The roots must establish themselves in the existing soil before the grass begins to grow. Insufficient watering and immediate foot traffic are major factors in sod lawn failure. The roots and grass dry up without sufficient watering, while immediate foot traffic crushes the roots and underlying soil.
Proper watering is the single most important step for maintaining a new sod lawn. Without sufficient watering, the grass wilts, roots dry, grass turns brown and the sod strips shrink from moisture loss.
Water the sod daily for the first seven to 10 days after laying the sod; twice-daily watering might be needed in hot drought periods. Water the lawn for 15 to 20 minutes at a time in each area, or however long is needed to ensure the water penetrates a few inches into the soil beneath the sod. Lift back a corner of the sod in several places throughout the lawn to check for water penetration.
After 10 days, switch to watering every other day, but increase the length of watering to about 30 minutes in each area. Continue reducing watering frequency every seven to 10 days; next, water twice weekly and then once weekly. Apply 1 inch of water weekly as a general guideline to avoid overwatering the sod, but adjust this amount if the lawn shows signs of wilting. When the sod is well-established, you should only need to apply water during periods of drought when there is insufficient rainfall. Check for signs of wilting to indicate a need for water.
Fertilizer provides the nutrients needed for the sod to grow well in its new space. Starter fertilizer is applied to the soil before laying new sod, which means there is no need to apply fertilizer until four to six weeks after laying the sod. Look for a slow-release complete lawn fertilizer with high nitrogen, such as 10-6-6; the numbers refer to the percentage of nitrogen, phosphorous and potassium present in the fertilizer. A soil test can help determine the best fertilizer to use for the particular lawn.
Apply at a rate of approximately 3/4 to 1 pound of nitrogen for every 1,000 square feet of yard space. Spread the fertilizer with a broadcast or cyclone spreader to ensure even coverage. Set the spreader to cast half the amount of fertilizer in a given pass and make two passes for best results.
Additional fertilizer applications can follow once every four to six weeks as desired, with a final light fertilizer application in mid-fall. Early spring fertilization is not necessary, but a mid-spring application around May helps continue growth into summer. At minimum, it is recommended to fertilize a lawn a minimum of twice annually -- once in spring and once in fall.
In the first week after laying new sod, it is crucial to keep traffic off the sod so the roots get the best start possible. Foot traffic and play compact the soil beneath the sod, making it more difficult for the roots to spread into the soil. If foot traffic is a particular problem in your area, you might go so far as to erect temporary safety fencing to protect the new sod. When stepping on the sod in the first week is necessary for proper watering, start at the farthest corner and back your way off the lawn to prevent stepping on wet sod, which causes greater soil compaction.
Light foot traffic is fine after one to two weeks or when the roots begin to establish in the soil. Lift a corner of the sod to check for resistance, indicating the roots have taken to the soil. Wait at least one month after laying sod before using the area for regular play beyond light foot traffic and regular maintenance needs.
Frequent mowing helps encourage healthy grass growth and should begin within two weeks of planting. The grass' energy is concentrated on root establishment after laying the sod, but grass growth resumes when the roots establish. Wait until the grass reaches a height of at least 3 inches before mowing.
Set the mower deck height to 2 to 3 inches to keep the grass cropped close without scalping the sod. Cut no more than one-third of the total grass blade length at one time, waiting at least a few days before cutting to a shorter length. Follow the direction of the sod strips when mowing to avoid pulling it up as you mow.
Expect to mow the sod once weekly through summer and into fall. Sharpen the mower blades frequently to ensure a clean cut without tearing the blades -- torn blades are more susceptible to disease.