Enter a ZIP code to get product recommendations and information tailored to your area.
If your lawn doesn’t seem to be growing as well as it should, even though it’s being fed regularly, it may be because of either thick thatch or compacted soil (or both). In both cases, the grass is suffering because air, water, and nutrients aren’t able to move freely into and through the soil, and are having trouble reaching the roots. You can tell your soil is overly compacted if you can’t easily insert a screwdriver into it. When thatch (bits of grass that have died and gathered just above the soil line) is too thick, your lawn will feel spongy, and it will be difficult to stick your finger through to the soil.
Either way, you need to take action. If your lawn’s failure to thrive is due to compaction, you will want to aerate it. If thick thatch is the problem, you will instead need to dethatch your lawn. Here’s how to do both of these simple fixes.
Lawn aeration, coring, and aerifying are different terms you might hear for the same procedure. A core aerator removes plugs of soil from your lawn, which helps loosen compacted soil and allows vital air, water, and nutrients to reach the roots. You can either aerate your lawn yourself or call a lawn service. If you plan to DIY, rent an aerator (you’ll need help and a truck to transport it) and follow these tips.
You want to aerate the lawn when your grass is in its peak growing period so it can recover quickly—think early spring or fall for cool-season grasses, and late spring through early summer for warm-season grasses. If you have high-traffic areas or heavy clay soil, you will want to aerate every year. If you have sandy soil or your lawn is growing well, aerating the lawn can happen every 2-3 years.
Thatch is a layer of living and dead grass shoots, stems, and roots that forms between the green grass blades and the soil surface. Sounds kind of gnarly, we know. However, a half-inch of thatch is good for your yard; it provides insulation from temperature extremes, helps keep moisture in the soil, and gives it a protective layer of cushioning. It’s when thatch builds up to more than ¾-inch thick that’s the problem. Too much decaying plant material can lead to increased pest and disease problems (and reduce the effectiveness of control products), stop oxygen and moisture from reaching the soil and grass roots, and keep your lawn from draining properly. So when the thatch stacks up, some of it’s got to go.
You can hire a lawn service to dethatch your lawn for you or follow these steps to do it yourself.
The best time to dethatch your lawn is when it’s actively growing and the soil is moderately moist. For cool-season grasses, that’s early spring or early fall. For warm-season grasses, dethatch in late spring through early summer (after the second mowing). That's when your grass is growing most vigorously.