With damaged lawns in the news lately, I thought I would share tips on renovating lawns this spring from fellow University of Illinois Extension Horticulture Educator Chris Enroth.
Spring is a time when we must go into landscape rehab mode. Mother Nature has shown her friendly side with the warmer winter temperatures and a handful of good rain and snow events. With the soil moisture up and temperatures warming, it is time to think about overseeding your lawn.
When overseeding, first analyze your soil. If your soil has become compacted or is very heavy clay, it is best to aerate prior to seeding. Hollow tine aerators work the best. Soil tests are an excellent way to determine your fertilizer needs and soil amending practices needed for optimal growth. Contact McLean County Master Gardeners at their walk-in Help Desk located at the University of Illinois Extension office for soil testing kits.
Overseed after aerating. If there are any bare spots I typically rough up the soil with a hard-tooth rake to provide good seed-to-soil contact.
Finally, I spread a thin layer of compost across my lawn. You can do this by hand or use a broadcast spreader. Due to costs of compost and what I have on hand I usually apply a depth of less than an inch, but you could go up to an inch. After spreading the compost I will drag a leaf rake over the lawn to ensure the grass seed makes good soil contact and to work the compost down into the turf. Be forewarned, I have been told, though I have never seen this, that spreading compost on a lawn on a hot sunny day can heat up that black gold and burn your existing turf.
And of course when overseeding do not forget to keep the seedbed moist, not saturated! A deep watering is not as essential at this point. As the seed germinates and becomes established you can decrease your watering frequency while increasing the watering time. Mow your turf after the new grass seedlings reach 2 or 3 inches. Cool-season grass prefers a cutting height between 2 and 4 inches.
Another tip for homeowners from the Lawn Talk website is to allow lawns to go under some drought stress in the first few warm days of spring. Allowing lawns to start to go under mild drought stress actually increases rooting. You can determine stress by watching for footprints remaining on the lawn after walking across it.
Go to the Extension website LawnTalk for more information on renovating your lawn. http://extension.illinois.edu/lawntalk/index.cfm