How to... Aerate Your Lawn

What is Lawn Aeration?

Lawn aeration refers to the process of creating channels in your lawn that enables air and water to circulate around the soil and grass roots more freely. This benefits your lawn in a number of ways but primarily the enhanced circulation of oxygen and water around the soil promotes deeper root growth, reduces thatch build up, helps your lawn to breathe and should definitely be part of your lawn care regime.

Most lawns will only require aerating when compacted soil becomes a problem. The soil can become compacted in a number of ways but the most common cause is heavy foot traffic, or if you have a soil that contains a lot of clay. Lighter soils that contain more sand and are richer in organic content are far less likely to become compacted unless susceptible to particularly heavy foot traffic.

Why do I need to aerate my lawn?

Over the years your lawn is likely to be become hard and compacted for a number of reasons including being used for sports or as a children's playground. When the soil used on your lawn becomes compacted, the pores which carry air and moisture around become much smaller. This reduced air and moisture infiltration is what eventually damages the health of your lawn.

The roots of your lawn require oxygen and nutrients in order to grow but if the soil becomes too compact for the air to circulate the oxygen can not get to the roots thus causing you problems. The other negative effect caused by heavily compacted soil is your lawns inability to absorb water or moisture to its deep root levels. Lawn aeration may also be required on soils that are made up heavily of clay as the air circulation and infiltration will be much more difficult with this material anyway due to the soils composition.

Poor root development, lack of oxygen and nutrient circulation can all leave your lawn looking a little worse for wear but these are not the only reasons to aerate. Thatch or thatch build-up can cause numerous problems for your lawn but can be combated using core aeration. This works because the cores of soil that are left on the thatch surface after aeration release microorganisms which break down the thatch and return important nutrients to the soil.

What are the Benefits of Lawn Aeration?

• Enhance water infiltration
• Prevent the loss of lawn food or fertilizer due to run off from heavily compacted areas
• Increase water, nutrient and oxygen uptake
• Improve root development
• Encourage decomposition and breakdown of thatch by microorganisms

When do I need to aerate my lawn?

Typically the best time of year to aerate your lawn will be during the spring or autumn season between March and May or September and October, however, the perfect time to aerate your lawn may depend on your location. For gardeners in the UK Spring is the best time for lawn aeration as there will be more light, water and soil resources at this time of year.

One of the best ways to assess whether or not your lawn requires aerating is to remove a section of the lawn and examine how deep the roots are growing into the soil. If the roots are only reaching a couple of inches into the soil then it is likely that the soil is compacted and that it needs aerating.

Another way to test your lawn is to insert a large screwdriver into the lawn and judge how much resistance you receive. If the soil is compacted you it will be very difficult to insert the screwdriver fully and you should think about aeration.

How often do I need to aerate my lawn?

Typically, and according to most experts, you should only have to aerate your lawn once every couple of years but if your lawn is used heavily you may want to consider aerating it at least twice a year.

When you decide to aerate your lawn will also depend on the age of the lawn itself as newly laid turf can benefit immensely from core aeration, although most experts recommend that its should not be aerated in the first year.

The quality of the soil will also determine how often you should aerate your lawn in order to keep it healthy. Aerating your lawn before applying fertilizer will improve the effectiveness of the applied nourishment.

When Should I not aerate my lawn?

Lawns that are not heavily exposed to compaction inducing events may not need aerating and in these instances the natural cycle of winter freezing and thawing and insect movement within the soil will naturally loosen lightly compacted soil anyway.

How do I aerate my lawn?

Lawn aeration can be carried out in a number of different ways and can be done either by hand, using specially adapted lawn aerator shoes or using mechanical lawn aeration machines. Core aeration involves the removal of small cylinder shaped cores which are essentially sucked out of the soil by hollow spikes or tines which are forcibly pushed into the soil by either a mechanical device or hand held or shoe aerator.

Core aerators typically will drill holes in your lawn of approximately 1/2 to 3/4 inch in diameter and 1-6 inches deep and 2-6 inches apart. Core aerators are more heavily recommended for lawns that are particularly compacted, exposed to heavy usage or that are prone to thatch build up.

Other aeration techniques include the insertion of solid spikes into the ground (such as the spikes or tines of a garden fork) into the soil. This method does not remove cores from the soil and is more suitable for lawns that are in better condition or that are aerated frequently.

When aerating your lawn you need to ensure that the soil is moist but not too wet. The moisture will allow the tines to penetrate the soil much deeper but if the lawn is too wet the soil will stick to the hollow tines and limit their effectiveness. If your soil is particularly dry you should thoroughly water it 2 or 3 days before your intend to aerate it allowing the soil to become moist but not soaked.

Where can I get lawn aerating equipment?

You can get your hands on numerous types of lawn aerators from most reputable garden centres with online garden centres offering some of the best deals. Depending on the condition of you lawn a great alternative to mechanical aerators are the cleverly adapted lawn aeration spike shoes which not only help to aerate your lawn but are also a great way to stay fit around the garden. If your lawn demands something a little more powerful then there are plenty of alternatives including rotary lawn aerators and heavy duty hollow tine aerators.

What do I need to do after I have aerated my lawn?

In order to get the most from your aeration efforts it is a good idea to apply a fertilizer or compost to your lawn as the aeration enables the lawn food to be absorbed much easily and the nutrients will be taken straight to the roots.  Also take a look at our Guide to the Perfect Lawn for more helpful ideas.