Thatch as defined by Dr. James B. Beard is “a tightly intermingled layer of dead and living stems and roots that develops between the zone of green vegetation and the soil surface.”
Dethatching is an aggressive approach to removing thatch and should be done correctly and at the right time of year so that the lawn can recover. Dethatching is not recommended annually. If your thatch layer consistently needs to be addressed there are cultural practices that need to be changed i.e. fertilization, mowing practices.
A proper evaluation from a professional on whether or not your lawn needs dethatching is a pre-requisite. We commonly field calls for dethatching from clients that simply want it done because they think it is the right thing to do. A professional should follow the following criteria to determine whether or not you are indeed in need of Lawn Dethatching.
Your lawn evaluation should involve:
- Asking you about your current and historical lawn care practices i.e. watering, mowing, fertilization
- Providing a site visit to visual analyze the thickness of the thatch layer and the condition of your lawn.
- Bringing you on the lawn and report/show you what they have found.
Encouraging a natural process of breaking down thatch to provide organic matter to the soil is a recommended organic practice. Healthy organic lawns have natural mechanisms in place to manage the thatch. I read a great article from Phil Nauta encouraging organic practices to manage thatch.
A good rule of thumb is ½” thatch layer. Maintaining the correct thatch layer is key ingredient to a healthy lawn. When the thatch layer exceeds that amount it can restricts the flow of water, nutrients, and air from moving from the soil to the air.