University of Illinois Extension

Lawn Recovery from Summer Drought

If there was ever a year in the decade where your lawn may really need a tune up, it will be 2012, said a University of Illinois Extension horticulture educator.

"Nearly the entire state has suffered from a lengthy drought and coupled with high temperatures sent your lawn into a dormant state," said Richard Hentschel. "Lawns going dormant is expected, making the lawn so difficult to maintain, though, has been the intensity of the heat and the lack of water. "

A mixture of green and fading straw colored grass blades appear before the lawn goes totally dormant. In a typical year, cool temperatures and the return of rain would be all it took to see that green lawn show up again.

"The late summer and early fall of 2012 will likely take more resources, time and energy to bring the lawn back," he noted. "Even before you get your hands dirty, putting a plan together will help you get through the process. For starters you are likely to find that even though the lawn was relatively weed-free before it went dormant, you will see those little islands of green in an otherwise brown sea of grass. Your goal is to get the grass back and not worry about those opportunistic weeds until much later or even next year."

If the lawn has received as little as one-half inch of water a month, the crowns are still alive and recovery will be easier. If the lawn has gone without any water, chances are you are going to find areas that are completely dead and a strong renovation plan is in order.

"A good beginning is to top-dress the lawn with a good quality black dirt or compost to provide a base for the new hybrid seed that will be needed to sprout and start the establishment process," Hentschel said. "Composts will provide water holding capacity and naturally contain a level of nutrition. An alternative to top-dressing is to use a machine that places the grass seed directly into the soil just below the surface. Contact your local rental company to see about availability and consider sharing the cost with your neighbor."

If a total renovation is in your future, then this is the time to be sure any soil amendments are added to the soil profile and that those areas that have held water get corrected with proper grading.

Starting the planning early also allows for a soil test to be taken. Soil tests reveal the soil pH, levels of nitrogen, phosphorus and potassium and commonly the percentage of organic matter.

"It is much easier to get those needed amendments and nutrition into the yard before the sod is laid or the seed put down," he noted. The next part of that plan is to decide if you are going to use hybrid seed or lay sod. Clearly there are advantages to each. Sod gives you that immediate impact and may be appropriate for the front yard, the public side of the home, or if desired, the entire yard. A seeded lawn provides the flexibility of matching the correct grass seed mix or blend to the site. Areas that were once full sun are now part to full shade perhaps and full sun blends or mixes will not be as successful as you want them to be.

"A critical part of your lawn restoration will be the watering used to establish either the sod or seed," Hentschel said. "Grass seed takes several days to sprout and emerge. This could be as little as five to seven days or up to 10-14 days, depending on the species of grass seed used. During this entire germination process the seed must be kept moist, yet not overly wet.

"Sod as delivered and laid is alive with a limited amount of roots. The sod is very dependent on that water to begin the process of growing new roots from the living crown. That energy comes from the green grass blades and the water supplied. If watered too much the sod can grow mushrooms and be way too soft to walk on while you are moving your sprinklers. Too dry and you will see the sod shrink and cracks open up between the rolls of sod besides seeing dead spots or streaks begin to show up."

The sod will need to be watered so that the soil below the sod gets moist to encourage the sod to root into the soil profile within just a couple of weeks, he added.

As the seed and sod establish in your yard, your watering practices will need to change to accommodate the changes in the sod and seed as it establishes.

"The last part of the restoration will be the first mowing," he said. "It is important that the seed or sod does not grow too high before that initial mowing. Oftentimes water is withheld for a day to firm up the soil and then resume the watering after the mowing is complete.

"A mowing detail that is commonly overlooked is the condition of the mower blade. Young grass plants can literally be torn out of the soil if the mower blade is dull. You won't be able to tear up sod, yet you can brown the cut edges with that dull blade."