Jeff Ball says---While the gardeners are curled up with their plant catalogs filled with Latin names, we yardeners have some planning to do ourselves for the coming growing season. We need to evaluate our lawn to determine whether we might need to add some grass seed sometime in late May.
Few mature lawns in Metro Detroit have turf that is as dense as brand new sod, but that should be the goal. Dense means when you spread the grass blades apart with your hands, you cannot see the soil. There are at least three reasons to take steps to make your turf as dense as it can be.
Thick turf mowed tall (higher than 2 inches) seldom has any weeds, including crabgrass. Every square foot of lawn will have anywhere from 10,000 to 20,000 weed seeds in the top 2 inches of soil, and all they need to germinate is light. When the grass is thin and mowed short, the most common situation in American lawns, weed seeds will germinate in large numbers, especially crabgrass. Thick, dense turf grass has few weeds.
Turf that is dense and mowed tall will become habitat for the three most important groups of beneficial insects in the home landscape -- ants, spiders and ground beetles, which I discussed in my column two weeks ago. If the grass is thin and cut short, there are few good guys in residence because they are vulnerable to their own predators. If the good guys are in camp, because they are protected by thick grass, they will consume 80 percent of all the eggs laid each year by the three most common insect pests in the lawn -- Japanese beetles, chinch bugs and billbugs. Thick, dense turf grass has few pest insects.
Finally, a lawn with dense turf will always look better than a lawn that is thin, especially right after it has been mowed. Thick, dense turf grass has lots of admirers.
The only way to make a lawn as dense as sod is to plant more grass seed. That process is called overseeding and should be a routine every four or five years. However, overseeding is hardly ever performed on home lawns. That is strange because golf course managers and athletic field managers will overseed every year to keep their turf dense. For some reason, the importance of that technique never filtered down to us yardeners.
Overseeding can be done in the spring, around Memorial Day, or in the fall, around Labor Day. While I'll discuss overseeding in more detail in a few weeks, the basic steps are to mow the grass as low as your mower will go. Then rake up all the debris. Next, spread grass seed and then water it twice a day for two weeks. The lawn can be mowed when the grass reaches 3 inches in height. Now mow tall.
If you have two acres of lawn, you are not likely going to be overseeding that entire area all at once. I suggest folks with large lawns spread the task over a few years. In the spring, overseed the front of the house. In the fall, overseed one side, and next spring, overseed the other side. When you get time, you can then deal with the back yard. It may seem like a lot of work, but the benefits are worth the effort. Once a lawn has become dense, the overseeding job four years from now is much easier.
There are two issues to deal with before the overseeding process. If your lawn has more than 20 percent weeds, you will need to take care of them first, about two weeks before the overseeding job. If your lawn is uneven with bumps and dips, you can even things up by filling in the low spots with topsoil.
The solution to a bumpy lawn is not to roll it with a lawn roller. Lawn rollers do more damage to the structure of the soil under a lawn than any other tool I know. Yet, every spring I see gardeners and yardeners alike out there rolling out their lawns before the soil dries out thinking they are doing a good thing. In fact, rolling a lawn when the soil is wet causes such serious compaction that even aerating cannot fix. Get rid of your lawn roller.
Jeff Ball, a Metro Detroit freelance writer, has authored eight books on gardening and lawn care. You can visit his yard care Web site at www.yardener.com and his blog at E-mail him at jeffball@usol.com.