The amount of water required to get your home lawn growing varies based on the following factors:
- soil moisture content
- soil and air temperature
- wind
- germination requirements specific to grass seed type
The same watering methods will apply whether you use seed, sod, plugs, or sprigs to establish a new lawn.
Soil Conditions
Heavy clay soils soak up water slowly but can be loosened by incorporating organic matter like peat moss or compost. Organic matter also improves sandy soil by improving water and holding more nutrients.
Watering Newly Planted Grass Seed
Grass planted at suitable times uses water more efficiently during establishment. September is ideal for cool-season grasses just like tall fescue and Kentucky bluegrass. Spring is often too early. Summer is the preferred time for planting warm-season grasses, including Bermuda grass, zoysia grass, and buffalograss. Seeding rate is important. If grass seed is planted too heavily, individual plants contend for moisture. When planted too thinly, establishment time may be slowed. Before planting grass seed, make sure your soil contains adequate moisture. Before planting, follow these steps to ensure good soil moisture as well as good incorporation of organic matter and fertilizer:
- Wet soil thoroughly and let drain for 2 days.
- Roto-till soil as deep as you possibly can.
- Wet soil again and let drain for an additional 2 days.
- Roto-till once again.
- Add organic matter and grass fertilizer over tilled soil.
- Roto-till one more time and as deep as is possible.
After seeding, keep grass seed moist until it finally germinates and becomes established. Initially, maintain the surface moisture of your seed bed with regular, light irrigation. Reduce irrigation if rainfall occurs. Light watering at least 2 to 3 times daily may be necessary to hold moisture in the seed bed. Grass seed that begins germinating and then dries out might die, so keep that seed bed moist.
Water newly seeded bluegrass or tall fescue in the late evening during the fall months. This will make water use more efficient by keeping the seedbed moist into the following morning. In much cooler weather of early to mid-fall, watering in the evening is less likely to spread disease.
As Your Grass Grows
After your young grass starts growing, increase the time between irrigations while also increasing the water used each time. When germination is complete and your grass is one inch tall, lengthen the watering interval to every other day, applying ¼-inch of water every time. (Read our How Long to Run Sprinklers on Your Grass post for how to measure water output in inches.)
In the second week after complete germination, water every third day. Apply ½-inch of water per irrigation. Afterward, 1 inch of water every 5 to 7 days should retain the new grass plants. If you are located in a hot and dry region, you will have to water more frequently.
When Your Grass is Mature
Both sodded and seeded cool-season grasses, such as tall fescue or Kentucky bluegrass, must be watered on a regular basis throughout the first summer after planting. Warm-season grasses like Bermuda grass, zoysia grass St. Augustine, and buffalograss also require regular watering during establishment, possibly everyday once hot temperatures start hitting.
Newly Laid Grass Sod
Water newly installed grass sod just like you would a newly seeded lawn – frequently enough to keep the contact area between sod and soil moist until new roots knit into the soil. When the sod is unable to be lifted by hand, it is rooted. As roots grow deeper, extend the watering interval.
Grass Plugs or Sprigs
Water plugs and sprigs just like seeded lawns. Keep soil moist until rooting has occurred, then increase the time between waterings.