With the hot, dry summer, many lawns were brown and dormant. The last couple weeks, however, we’ve gotten at least an inch of rain, so our lawns in this part of the state are starting to green up again. Kentucky bluegrass, which is very common in lawn seed mixes, is a cool season grass; anytime the temperatures get too warm, bluegrass will protect itself by going dormant. A half inch of water every two weeks is enough to keep the crowns alive and green under the brown blades. In order to keep lawns from going dormant in heat and drought conditions, a deep watering of one inch per week is needed.
After the temperatures lower and the rain is more frequent, grass will come out of dormancy and turn green again. Unfortunately, patches of lawn may have died during the drought. Mid-August to mid-September is an ideal time to put down grass seed and repair any of the dead patches in the lawn, or seed a new lawn, because the night temperatures are cooler and the rainfall is usually fairly regular. To reseed bare areas, first lightly rake up the brown, dead blades. You may want to add topsoil or organic matter, such as compeat, which can be rototilled in. There are sun and shade mixes available; typically, sun mixes will have more Kentucky bluegrass in them and shade mixes have more fescue. Apply the seed at the rate explained on the bag and add fertilizer on top. The best fertilizer for establishing a new lawn is high in phosphorous, which is the second of the three numbers seen on fertilizer bags. (nitrogen-phosphorous-potassium) This promotes good root growth and helps the grass to get established better. Once the seed and fertilizer are down, rake it in at about a 1/8″ depth and tamp it down to ensure good seed to soil contact. To keep it from washing away, put down straw or penn mulch on top, which can be taken off once the grass seed has sprouted. Watering should be done fairly frequently- almost daily in fall- until the grass has established itself. Once it reaches a height of 3 to 3 1/2 inches, it can be mowed.
For lawn that has greened up after a drought, a fertilizer application can be put down around Labor Day weekend. The application should be high in nitrogen to help the lawn continue to grow and stay green through the fall. Aeration can also be done in fall or spring, and should be done once every year or every other year. Aeration promotes deeper root growth in turfgrass.
If you have any lawn questions, please call the garden center at 733-8223, or stop in to talk to a garden center representative. Garden center hours are Monday through Saturday from 8-6, and Sunday from 10-4.