Lawn aeration

Why aerate the lawn

The benefits of aeration in the form of hollow tining can be seen in the soil profile of the above image . The lawn has been hollowtined then top dressed. The top dressing has been brushed down the hollowtine hole completely filling it, improving the drainage, airflow, rooting etc, resulting in a healthier lawn.

All soil types are vulnerable to compaction although heavy clay soils are more prone to compaction than light sandy soils due to the small soil particles.

Compaction is basically a result of compression placed on the soil particles which causes a breakdown in soil structure resulting in lack of air.

Compaction causes the pore spaces in the soil to become small thus reducing the amount of air held in the root zone. This inhibits drainage, has a negative effect on rooting, encouraging shallow rooted grasses which in turn will reduce drought resistance. Over a period of time lawns can become compact especially if they are heavily used.

Lack of air also has a negative effect on micro organisms in the soil, which need air to survive. Micro organisms are required to break down the thatch layer and return nutrients to the plant. Overall a lack of air has a detrimental effect on the health of your lawn.

The benefits of aerating a lawn

A healthy well aerated lawn has a number of benefits, these benefits include:

• An increase in desirable bent and fescue grasses over annual meadow grass. Bents and fescues being easier to maintain, are more drought resistant, require less fertiliser, are more disease resistant (especially fusarium patch). They produce a better quality lawn (Bents and fescues are the favoured grasses on golf and bowling greens)
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• An improvement in rooting, producing a healthy drought resistant lawn.
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• Encourages micro organisms which are beneficial to soil as they aid thatch breakdown. They are also beneficial in helping with disease resistance as they inhibit the pathogens that causes the disease.
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• Aids irrigation by helping the water go down to the roots and reduces surface run off.
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• If lawn aeration is carried out before top dressing it helps improve the soil structure as the top dressing fills the channels created by the aeration.
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• Can be also beneficial to drainage by creating channels for the water to penetrate and drain away.

When to aerate your lawn

To get the most benefit from lawn aeration it is best carried out when the soil is warm, late summer being a good time for aeration. Aeration will help with the drainage during the winter months and help encourage healthy roots.

However aeration can be carried out at any time during the year. If your lawn is suffering from a drought spiking the lawn during the summer will aid water to penetrate to the roots.

The different types of lawn aeration

There are many types of lawn aeration and many different implements and machines on the market. We will explain the different types of aeration and the different benefits that each have. They are as follows:

• Spiking or Solid Tining
  Probably the most common type of aeration on a lawn due to the fact that most people have a garden fork. However there are machines available for this task. Spiking is particularly useful during the summer months prior to irrigation to help the water penetrate into the soil profile. Spiking is preferred to slitting in the summer due to fact after slitting, the slits are prone to opening up if it is dry. 
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• Slitting
  Slitting is not as common as spiking for lawn aeration however there are benefits of slitting over spiking. They can generally go deeper that spiking and also has the added benefit of root development as it prunes the roots. 
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• Hollow Tining or Hollow Coring
  This process involves the removal of cores from the lawn. The main benefits if this method would be to remove thatch. It is also very beneficial before top dressing as it leaves larger holes than other types of aeration. Therefore it is easier to work in top dressing through the holes and into the root zone.

A proffesional pedestrian aerator, machines similar to this are available for hire for large gardens.		An area of turf after hollow tining. Note how the holes are larger than normal aeration making it ideal to rub in top dressing.