Lawn Dethatching

Over time, lawns accumulate thatch. Thatch is a layer of slowly decomposing grass, dead roots, and other yard debris that's picked up by your mower and tossed back onto the grass. Thatch can accumulate even if you sweep or use a mulching mower, however the build up may not be as quick. The accumulation of thatch over time prevents water and other nutrients from getting through to the roots of your lawn. Accumulation of thatch, like the compacted soil, also gives insects a great place to hide.

A light layer of thatch, one-fourth to one-half inches deep, is actually beneficial to your lawn. It protects the soil from changing temperatures and adds to the resilience of the lawn, which means when you step on it, it springs back instead of compacting the soil. However, even too much of a good thing can be damaging. When your thatch becomes too think it acts as a thatch roof would. It repels water and any other nutrient you try to give your lawn. Thick thatch can prevent water from ever reaching the soil, which results in the grass roots growing in the thatch, instead of the soil. Since the water in the thatch evaporates much quicker than that in the soil, your lawn will become susceptible to drying out quicker than if the roots were planted firmly in the soil.

Some grasses produce more thatch than others. For example, lawns composed of creeping grasses will build up thatch quicker than those that are not. Notorious thatch builders include: Bermuda grass, St. Augustine grass and Zoysia grass. However, dethatching is not recommended for certain type lawns, such as lawns that consist of St. Augustine grass. Also cool-season grasses such as Bentgrass and Kentucky Bluegrass are excessive thatch producers. If your soil is extremely acidic, then any type of grass can build thatch quicker because the microorganisms that decompose the thatch are less active.

Since the thatch keeps the ground temperatures from changing a lot, insects and diseases thrive in thatch-covered lawns. Think about it. It's warm and moist and cannot be penetrated easily by substances used to control the insects or disease. What better place to live if you're a grub? Another problem with thatch filled lawns is that the mower will not be able to mow evenly. This will cause other problems such as scalping.

To prevent your thatch from getting too thick, dethatching is usually performed every other year. You can tell how much thatch has built up by using an aeration device to remove three plugs of soil. The top layer of the plug that looks kind of like peat is your thatch. If it measures more than one-half inch, it is time to dethatch. It's best to dethatch your lawn just before it begins growing the most vigorous for the season. For most states, this would be in the spring. If you have cool-season grasses, such as Kentucky Bluegrass, then fall is the best time to dethatch.

 

 

 

2583 W. Plains Rd
Mason, MI. 48854