Scarification reduces the build-up of dead grass matter, roots and moss, which can cause increased stress to your turf. It should only be done when the grass is growing well and once scarified, a lawn may need overseeding to fill patches where weeds would otherwise invade. If growth is slow, there is a higher risk that the gaps will be filled with unwanted weeds or weed-grasses. Encourage grass growth after scarification by overseeding and or fertilising. Find out more about scarification: https