Lawn Aeration

Hollow tine aeration is very effective on lawns suffering
from excessive thatch accumulation.

Lawns are quite similar to people in that they need air in order to survive and maintain good vigour. If there is a deficiency of air in the soil , then the health of the lawn is likely to suffer. Therefore it is important that the soil must be kept in good condition with routine aeration.

Reasons for aerating the lawn

• To relieve soil compaction. Over a long period of time the soil will become compacted. This is caused by people, machinery and other traffic on the surface of the lawn. This soil becomes compressed or compacted as the air is squeezed from the soil. Aerating the lawn can help rectify this problem by punching holes into the lawn to increase air space. Soil compaction is more problematic on clay soils than on light sandy soils.

• Improved rooting. Naturally, a soil that has adequate airspace is going to support a healthy root system. A good root system helps the grass withstand drought conditions as the roots are able to penetrate deeper into the soil. The roots can also tap into any available nutrients that may be present deeper down.

• Prevent the accumulation of thatch. Excessive thatch is one of the biggest culprits of poor lawn health. Thatch is a layer of organic matter that forms in the base of the lawn, between the grass and the soil. Too much thatch impedes drainage and restricts root growth resulting in poor growing conditions. A routine lawn aeration program can prevent and control thatch accumulation.

• Encourage a healthy population of micro organisms in the soil. Micro organisms or microbes are essential for a healthy lawn, as they break down thatch, help supress disease and  degrade soil toxins. These microbes thrive in soils that contain sufficient air movement. If air is lacking then they will slowly reduce in number and eventually dissappear.

• Improve drainage. Good drainage is very important to the overall health of the soil and lawn. If the water cant drain away then the soil remians wet and air is displaced, which in turn promotes poor rooting, encourages weed grasses and the build up of thatch.

• Improve gasseous exchange between the soil and atmosphere. Without good gaseous exchange and water movement the soil will simply stagnate, resulting in poor rooting,  and thatch build up.

• Promote deeper rooted grasses. If the soil is in healthy condition then this will help encourage and increase the amount of deeper rooted grasses within the lawn. These grasses require less maintenance as they can withstand drought conditons, are more resitant to diseases and in certain situations require less nutrient inputs to stay healthy.

As you can see from the reasons above if there is to be any chance of creating optimum growing conditons then a good lawn aeration program needs to be implemented. Without air in the soil then the battle will be lost right from the start.

Aeration machinery and implements

For the gardener there are various methods in which to aerate the lawn,  with a powered machine, a towed machine or a hand held implement.

• Powered lawn aerators. This type of lawn aerator is perfect for large gardens as they cover large areas in a short period of time. In most cases the tines are interchangeable. The obvious downside to this type of aerator is the cost, they are very expensive. It may be better to do a little detective work a see if a local garden center hires this type of machine.

• Tow behind aerators. These machines can be pulled behind a garden tractor to cover the lawn in a short period of time. On most of these aerators there is a weight tray, where weight can be added to help the tines penetrate into the soil. They are a cost effective alternative to powered lawn aerators. However they are not suitable for small lawns.

• Hand aerators. These type of lawn aerators range from push machines to a simple garden fork. They are ideal for small and tight lawns. Although they could be used on a large lawn, it would be very time consuming and labour intensive.

When to aerate the lawn

All lawns should be aerated at least once , preferable twice a year. The ideal periods for aeration are spring and autumn. Aeration should be incorporated into the spring and autumn lawn renovation programs, that can also include scarification, overseeding, moss and weed control and top dressing.