Thatch is defined as the layer of accumulated plant materials found between the soil and the green grass itself. Contrary to most beliefs, thatch is natural and a part of your lawn's growth process. It even has many beneficial elements such as aiding in the retention of water and nutrients. It's only when the thatch layer is in excess that problems occur. Thatch is in excess when it reaches a depth of 1/2 inch.
Cultural practices are usually the cause of excessive thatch. The two most common reasons for too much thatch are over-fertilization with high nitrogen fertilizers and improper mowing. The abundant top growth caused by over-fertilization and the buildup up clippings from mowing too short cause thatch to increase quicker than it can naturally decompose. Our lawns need approximately 4LB of nitrogen per 1,000 square feet per year, no more. Lawns should also be mowed to a height of no less than 2" in cool weather and 3" in hot conditions. Do not let your lawn become overly-long between mowings. Each mowing should remove no more than 1/3 of the grass blade.
The only way to check if your lawn has an excessive layer of thatch is to take a soil core from the lawn and physically inspect the thatch layer. If it is determined that you indeed have a thatch problem, the best method of control is core aeration. Aerate twice the first year and each fall thereafter. Core aeration makes "Swiss cheese" of the existing thatch and encourages natural decay of the existing thatch layer. Following correct cultural practices will also allow nature to aid in the thatch breakdown. We DO NOT recommend the use of de-thatching machines and power rakes. They work by ripping out the existing thatch. On clay-based soil, you will damage the good grass as well.
Core aerators are commonly rented at equipment rental stores or simply call us to provide all your lawn care needs.
Vande Hey Design Center
