How to Identify and Control Thatch
Thatch is mostly invisible to the naked eye, especially if you’re looking at your lawn from standing height. It grows right next to the soil at the base of your lawn, so thick grass carpets usually obscure it from view. However, if you get down close to the ground and spread some grass blades apart, you may see a mass of mossy, light brown fibers growing in a continuous layer across your lawn.
Lawns with excessive thatch may feel abnormally springy. If your lawn is still young, meaning it’s within a year or two of planting, you are very unlikely to experience thatch. This is a problem that develops slowly over time as a lawn matures.
Why Is Thatch Bad News for Lawn Care?
When it gets thick, thatch can prevent adequate moisture from reaching the soil, robbing your lawn’s root system of water. It can similarly prevent fertilizers from penetrating down to the roots. A thick layer of thatch can also cause insulation problems, making your lawn more vulnerable to temperature changes. In addition, this tangly mess provides the perfect hideout for pest insects and other nuisances that can damage your lawn.
Do You Need to Dethatch?
The good news is that thatch actually isn’t always a bad thing. A small quantity of thatch can help insulate your lawn and keep moisture from escaping. But as you’ve already seen, too much thatch can cause major problems. If the thatch layer on your lawn is more than half an inch thick or you’re noticing that your lawn seems to be drying out in spite of plentiful watering, it’s definitely time to dethatch.
Dethatching and Thatch Prevention Techniques
To prevent thatch buildup, make sure you don’t water too often. When you do water, you should provide a lot of moisture for the lawn that penetrates deeply into the root system. Regular mowing and core aeration help prevent buildup, too. Aeration is an effective technique to dethatch a large surface area, while raking by hand can help control thatch in smaller areas. It’s best to stay away from chemical dethatchers—they’re not actually that effective in most cases. Raking and other physical techniques are your best bet.