Dethatching removes the layer of dead leaves, grass, roots, and rhizomes that gathers between the soil surface and grass blades. Over time, thatch forms a thick cover that stops water and airflow from reaching the depth of the soil.
A small amount of thatch is reasonable and beneficial for your lawn. A thin layer of thatch will make the lawn more resilient against wear and tear, but too much thatch can cause problems to your lawn.
Dethatching can be a stressful process for the turf. If the root system have begun growing in the thatch layer, dethatching could end up removing a considerable amount of turf and leave brown patches on your lawn. This service should only be conducted when the grass is actively growing and the soil is moist.