[1] In compacted lawns, aeration improves soil drainage and encourages worms, microfauna and microflora which require oxygen.
Soil compaction makes it difficult for grass to develop long roots and disturbs both natural rainwater and artificial irrigation.
This reduces compaction in the soil, and the holes can stay open for a long time allowing air, fertilisers, and water to reach the roots.
The operator puts one foot on the step bar and push it downward, forcing the tines to penetrate into the soil.
Cool-season grasses (bluegrass, fescue and ryegrass) should be aerated in early spring or fall (March, April or September).