“Thatch” is the term given to the matted layers between the green vegetation and the soil surface. These are made up of the accumulation of dead stems, leaves, stolons, rhizomes, roots and lawn clippings, intermingled with the decaying organic matter. When this layer dries out it becomes ‘hydrophobic’ (waterproof). The matted layers then respond in a similar fashion to that of the thatched roof on the Robert Burns Cottage. Preventing moisture, oxygen, fertilisers, and other nutrients from penetrating into the root zone, where the lawn needs it the most. As a result of this you are encouraging “lazy” root development, creating “shallow rooting”. Your lawn will become prone to grass diseases (e.g. Red Thread & Fusarium) and dry out.
In order to rectify this situation you must first and foremost reduce and control the volume of thatch in your lawn. This can be achieved by scarifying the affected lawns. Badly affected lawns with a thick layer of thatch will need to be heavily scarified (restored), to the extent you are exposing the surface of the soil beneath.
After heavily scarifying your lawn it is strongly recommended to aerate it. This helps to relieve surface soil compaction and to create good seed-beds evenly across your lawn for sowing seed.
Scarifying a lawn with shallow rooting and a thick thatch layer will generally result in the lawn(s) being left thin, patchy or even in some cases, bare. The recommended final step in this procedure is to evenly dress with seed and soil/compost in order to ensure a good density of grass and to replenish your lawn(s).
Once this has been carried out it is essential to keep your lawn well watered. A minimum of 2 hours a day is advised for the first few weeks of the initial establishing period.