Choose grass seed that grows well in your part of Utah. Take into account how much sunlight your yard gets, as well as the average rainfall and temperature range. According to the Utah Division of Water Resources, Kentucky Bluegrass is the most popular grass in Utah. Warm season grasses Bermudagrass and Zoysiagrass can tolerate the extremely warm temperatures in southern Utah. Although Bermudagrass is popular in that part of the state, it is considered a noxious weed and is only permitted in Washington County.
Till the planting area to a depth of 4 to 6 inches. Utah soil ranges from pure sand to packed clay. Sand is very dry whereas clay soil has poor drainage and water pooling. Loosening up the soil is essential if you're working with a moist composition, such as clay, because there are virtually no air pockets under the ground to help the grass roots grow and spread. If you're not sure what type of soil you have, send a sample to Utah State University's Soil Analysis Lab. (See Resources.)
Amend clay soil in Utah to make it more suitable for grass growth. Use coarse sand (builders sand) and coarse organic matter such as aged manure or coarse compost. Cover the planting area with 3 to 4 inches each of the sand and compost. Use a little more course sand if you notice the soil is still on the wet and heavy side. Till the substances together, working to a depth of 4 to 6 inches.
Add at least 2 inches of organic material if you live in a part of Utah with sandy soil. Use shredded bark, peat moss, manure or compost to help the sand hold water and nutrients. Till the amendments into the top 4 to 6 inches.
Remove weeds. Pull them by hand or use an herbicide to kill them. If you use a weed killer, wait a few weeks to plant seed because it is more likely to die from the chemicals. Break up soil clumps that are larger than 1 inch in diameter because they will prevent the grass seed from germinating.
Spread grass seed with a hand or broadcast spreader, depending on the size of the planting area. Follow the recommended seed rate. According to Greenview Fertilizer, you should spread 16 seeds per square inch of earth. Too many seeds will fight for nutrients and too few will leave gaps.
Add a grass seed accelerator to the top of the sown lawn to help it grow. Rake the seeds gently with the back of a metal rake to cover them with 1/4 to 1/8 inch of soil. This soil will keep them in place and promote germination.
Water the seeds every day to keep them moist. Do not soak them and do not let water pool if your soil is claylike in consistency. You may need to water the seeds a bit more if you have the sandy soil present in many parts of the state. Pay special attention to watering the seed if you live in southern Utah because of the hot temperatures.
Water your new lawn according to a water demand curve. Utah lawns have a pattern that starts in the middle of April, peaks in July, then decreases steadily until the middle of October. For example, in June in North Central Utah, water for 21 minutes every three days. In Southwest Utah, water it for 27 minutes every three days. (See Resources for the schedule.)
Look for brown spots on your lawn. Utah's climate is arid, so there aren't many diseases that affect lawns. Typically, brown spots indicate a lack of water. Check for damaged sprinkler heads or another problem with your irrigation system.