Thatch Removal (Dethatching)
Thatch is a layer of partially decomposed plant material that build up on the soil surface. This layer of thatch decreases the turf vigor by restricting the movement of air , water and other nutrients into the soil. Excessive thatch also restricts root development and provides a suitable environment for insects and disease pests.
de-thatching of lawns is a mechanical process where the surface of the lawn is rigorously abraded by penetrating metal blades, tines or prongs. Dethatching make the grass stronger, thickened and less susceptible to disease. It also increases the level of water, air and nutrients into the soil. Overtime thatch build an environment that can encourage pests and diseases , Dethatching can help prevent these problems When de-thatching, not all thatch should be removed as a small amount of thatch is beneficial to the lawn. A lawn that has excessive thatch may feel spongy when trod upon. After removing thatch, it can be swept or raked up using a lawn sweeper.
Timing
If your lawn is bouncy when you walk on it, thatch is probably building up. Generally you can dethatch your lawn when the thickness of the thatch is more than 1/2 inch deep. To determine the thickness, you can remove a small square of your lawn to a depth of about 3 inches and measure the brown layer between the grass blades and the soil surface. Dethatching is normally carried out in autumn or spring.