A lawn aerator is a gardening tool which is available in various shapes and sizes. The earth in a lawn becomes compacted and hard acting as a wall and preventing essential elements like sunlight and oxygen from getting to the lower layers of a lawn. The lawn aerator facilitates water drainage in the lawn. The aerator promotes the proliferation of worms, microflora and microfauna which need oxygen. It does the job otherwise done by a hand held hoe. There are two kinds of hoes and these are the ones that make holes in the lawn and the ones that take out plugs of soil out of the lawn.
The hole making aerator is not as good as the one which takes out plugs of soil. The holes made by a lawn aerator with spikes start closing up after the lawn is watered with the expansion of the side walls because of the water. The basic idea of the lawn aerator is to break up the lawn compaction and to control the lawn thatch. Lawn thatch appears with the passage of time and contains organic dead tissues. This thatch prevents the penetration of oxygen to the lower level. Oxygen is necessary for the growth of a good lawn. The other reason for using a lawn aerator is soil compaction. Soil compaction leaves a hard surface which prevents rain water and lawn spray water to penetrate to a lower level. It also prevents the growth of new grass on empty patches in the lawn. A lawn aerator breaks down the hard surface and makes it easy for the grass to take root and for the water to reach the lower levels of the soil.
There are many versions of aerators. The two most popular basically consist of hollow tines or sharp pointed spikes fixed on a roller that is pushed either manually or through some motor which makes moving the machine a lot easier. The hollow tines take plugs of earth out and place them in front of the unplugged earth as the roller moves ahead. This allows water, sunlight and fertiliser to reach the lower levels of the soil. In the other version the spikes force holes in the lawn which leads to further compacting of the soil in those areas. The lawn aerator with the hollow tines is better because the hole made by this method last longer and the plugs taken out form a good layer above the lawn.
A simple hand held hoe can be used as a lawn aerator to make holes in the ground and for breaking up the turf in order to oxygenate it. An ingenious method is to wear sandals with long spikes while weeding and pruning. The spikes on the sandal make holes in the lawn while the gardener does other work in the lawn.
Man has discovered over centuries that turf needs to be dug up and turned over to allow it to get sunshine and oxygen. For ages this has been done with the short handled or long handled hoe. Modern technology has created big machines run by gasoline which work as a lawn aerator and manage to make holes in a lawn in a short span of time. People who are environmental friendly prefer the manual lawn aerator. This does the work and keeps the ecology green too.