Scarification
Some species of grass produce more horizontal growth than others and this can build up to a point where it needs to be removed to allow healthy growth. Scarifying is really a pruning process and is done using vertical blades that cut into the top of the turf mat.

The frequency of scarifying necessary depends upon the type of turf, and the maintenance regime. For example, a turf containing ryegrass needs very little, if any, scarifying because of the tufted growth characteristic of the ryegrass. A turf containing no ryegrass is likely to need scarifying at least every two years because of the lateral growth of bents, fescues, and smoothstalked meadowgrass. In addition, if the turf is regularly fertilised and watered the growth rate will increase, resulting in a faster build-up of the turf mat. In this situation lawns will benefit from scarifying every year, preferably during the early autumn.

Scarifying involves raking vigorously with a spring-tined or sharp-toothed rake, pushing it well down to pull out the dead grass or moss and break stem of creeping grasses. Scarify two weeks after using a moss-killer to remove the dead moss.

Aeration
Grass roots need air in order to support healthy growth. In a well-structured soil there are lots of natural air pockets. During wet weather the soil becomes soft and if the lawn is used heavily the soil structure is damaged, the air pockets are destroyed, and grass growth suffers. Aeration is a means of getting air back into the soil by punching holes into the lawn to a depth of about 100mm. All lawns benefit from aeration at some stage with heavily used lawns needing treatment more often. It is possible to aerate small areas with a garden fork or hollow tine, but it is very hard work! For larger areas it is better to hire a mechanical aerator or slitting machine.