What is Lawn Aeration

What is Lawn Aeration?

Aerating the lawn is the procedure of getting air into the lawn soil. De-compaction relieves the pressure between soil particles, making them less dense. They are the same for all intents and purposes, resulting in more air into the soil. These air spaces partially fill up and store the rainwater for use by the grass.

Why Aerate Your Lawn?

Aerating your lawn is one of the most beneficial practices for its health. It enhances drainage by alleviating soil compaction, enabling air and water to penetrate the grass roots. This process allows the roots to access oxygen and essential nutrients, promoting a lush, robust lawn. Additionally, lawn aeration helps to break down the thatch layer composed of dead grass stems and other plant material forming on the soil surface. Thatch can form a barrier that obstructs water flow from reaching the soil, but aeration creates holes that facilitate water absorption.

When is the best time to aerate a lawn?

The best times for lawn aeration in the UK are spring and autumn. During these seasons, the soil tends to be moist, making it much easier to create holes.

Many people in the UK choose to aerate their lawn in spring because it aligns with the grass's growing season, allowing it to recover effectively. With the UK's unpredictable weather, caution is crucial. If soil is overly wet, the holes created may not provide enough air flow or water to the roots, as the sides can quickly close over.

How to Identify and Address Lawn Compaction

Aeration relieves compaction by allowing air, rain, and nutrients to penetrate a hard surface, improving bacterial activity and helping reduce thatch. It also improves drainage from the surface, increases the water-holding capacity, and stimulates rooting and root depth, giving a more drought-tolerant lawn. If your lawn suffers from premature drying, poor drainage, or moss invasion, then aeration will help.

For more information, read our lawn advice on how to aerate the lawn.

How Often Should You Aerate Your Lawn?

This all depends on the grass quality and the soil type in your lawn. If your soil is hard and compacted clay, improving the entire lawn once a year is advisable. For sandy soil, you often don’t need to aerate the whole lawn; simply working on small sections is usually sufficient.

Take action throughout the year, though. If you see a layer of water on top of your grass, the water isn’t draining well, or if your grass doesn’t look healthy, it’s time to get to

Aerating Older Lawns

If the lawn is old (20 years plus) and hasn't been aerated, the compaction will be so severe that aeration will not cure the problem. In this instance, the only remedy is to dig over the lawn and soil to a depth of at least 15cm. This aerates the soil and removes the compaction, enabling you to create a new lawn with all the benefits of ease of care and improved health and looks that that brings.

For more information, take a look at our lawn advice on how to restore an old lawn.

Lawn Aeration and Soil Types

You will achieve meaningful aeration on light clay to very sandy soils. The ‘squeezing’ effect is reduced due to sandy particles, which become well agitated, enhancing air flow and partially alleviating compaction. However, sticky or heavy clay soils behave differently. In these cases, the ‘squeezing’ effect merely shifts the compaction issue without offering any real advantages.

Using a hollow tine aerator to create cores is a better approach for these soil types. This method involves removing hundreds or thousands of cores, about 2 inches long and ½ inch in diameter, from the lawn surface. Sadly, the soil that could benefit most, sticky and heavy clays, often clogs the aerator, making it ineffective.

The only type of hollow tine aerator that does a reasonable job is the petrol-powered drum aerator, which can be hired. It is also beneficial to hollow tine other soils, though you may be wasting your time with sandy soils where spiking is the better method.

For more information, see our lawn advice on how to test for Clay or sandy soil in your lawn.

Spiking is a standard method of lawn aeration. But please be careful, if you stick a garden fork or use a lawn spiker on your lawn, you may make a hole. You might be wondering where the soil at the sides has gone. The fork has pushed it aside, causing it to become more compacted! So, is this method worth it? That depends on the type of soil you have in your lawn.