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Forking a Lawn – Aerating Lawn Correctly

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Have you ever wondered how to cultivate a beautiful, green lawn? Then forking a lawn is one of the best ways to help achieve this.

Aerating the lawn is one of the most important and effective ways to achieve and maintain a healthy lawn. It will help remove thatch and enhance the flow of nutrients, water, and oxygen to the grass’s roots. 

5 Key Benefits of Aerating Yout Lawn

  1. Alleviate compacted soil: aerating reduces soil density helping the grass roots to penetrate deeper.
  2. Improves soil structure: The reduction in soil density with the addition of sand into the cores improves the soil structure and drainage.
  3. Improves root access to oxygen and water: Aerating allows the grass roots access to moisture and oxygen as both can grow deeper into the soil substrate.
  4. Manages to reduce thatch build-up: Thatch prevents the grass from accessing nutrients and can be the cause of fungal infection. Aeration allows the micro-organisms in the soil to come to the surface and help decompose their thatch layer.
  5. Allows a thicker lawn to grow back: The improvement of soil structure drainage and access to the nutrients in the ground, allows the soil to grow back thicker and stronger. This can be enhanced by overseeding.

What is Lawn Aeration?

Aeration is a process of opening cores in the soil, each core is about a quarter to three-quarters of an inch in diameter and three to four inches deep (but can vary). This can be done using a special aerating tool or by forking a lawn using a communal garden fork.  

Aeration opens the soil to allow air, water, and nutrients to penetrate deeper and relieve soil compaction. This aids in the development of deeper roots, resulting in a more robust lawn.  

Aerating a lawn is done when the soil becomes compacted from heavy foot traffic and mowing. When the soil becomes compacted it prevents water from soaking in, air from penetrating it, and fertilizer from reaching the soil’s root zone. Soil compaction also prevents roots from growing deeply, thereby reducing the grass’s ability to produce food from photosynthesis.  

Lawns that have compacted soil tend to have a much higher thatch content. Too much lawn thatch or dense organic debris lying under the lawn’s surface may also deprive the grassroots of vital nutrients.   Aeration should be done to a lawn as soon as it is obvious that the soil has become compacted. If you have had particularly heavy footfall or have increased your mowing then you should aerate it. 

A Guide to Forking a Lawn

Any lawn, whether it’s a casual gathering spot for the family or a more formal part of the landscape, may benefit from learning how to properly aerate it. In times of drought or waterlogging, a well-aerated lawn will be more resilient and simpler to maintain and mow in the spring and summer.

A lot of articles will talk about choosing the type of aerator to use. There is no doubt that there are many good manual and mechanical aerators both core and spike you could use. However, unless you have a specific need and provided that your lawn is not too excessive in size, the humble garden fork is a perfectly adequate tool for the operation.

A Guide to Forking a Lawn

Assessing Your Lawn

Aerating is the process of spiking the lawn in order to allow more air and water to penetrate the grass’s roots. It’s especially crucial to pay attention to the parts of the lawn that see the greatest wear and tear, typically as a result of children’s activities and dogs’ movement over it, and that are particularly compacted.

As a result, before you begin, inspect the grass to determine what sort of condition it is in after the summer season. You’ll be able to determine when the grass is scant or stunted because of your visual cues. Meanwhile, if you see pools of rainwater instead of the water being absorbed, compaction may be present. However, you may also conduct a test by inserting a spike into the grass. There is most certainly a compacted layer present if you find it difficult to push it more than a couple of inches at first but below that, you get less resistance.

Preparing the Lawn for Forking – Getting the Lawn Ready to Aerate

 Make sure that your lawn is in good shape and is properly prepared before beginning the aeration procedure. Raking garbage, twigs, and leaves off the lawn is an important part of the preparations. You should also cut your grass to make it simpler for the insects to penetrate. It is also important to remember to switch off your sprinklers if you have them before starting to aerate your lawn.

You should pay special attention to delicate regions. In the event that you have portions of your lawn that attract more traffic than others, it is suggested that you pay particular attention to such regions. In order to achieve the best possible result, you may even go over these areas a second time.

Spiking Your Lawn 

An excellent time for aeration is after rainfall or watering (irrigation) as it is a much more difficult job on harder ground and the moisture will make the procedure much simpler. On the other hand, you don’t want the lawn to be too wet or waterlogged either.

When you are ready to start forking your lawn start working the fork tines into the soil at around every twelve inches, working up and down the lawn in a methodical way.

Fill Holes With Sand

When you have finished spiking the soil, you can use sand to fill up the holes. This will significantly enhance drainage, which is particularly beneficial when you have heavy clay soils or if your grass is prone to becoming waterlogged. It is best to use masonry sand for the purpose, but it is important to ensure that there is no debris in it.

If you have especially heavy clay soil you might want to consider adding calcium sulfate dihydrate (gypsum) as this can aid in the decompaction and improve the structure of clay soils.

If your soil is normal or light sandy soil, you can instead use a ready-mixed top treatment. This can help to smooth out any lumps or unevenness on the lawn’s surface.

Scarifying the Lawn

An optional process, after you have completed aerating is to scarify a lawn. The reason that you may want to do this is it will help to remove the thatch and moss from a lawn if the thatch and moss is more than about a quarter of an inch thick water and any fertilizer you use may not be able to penetrate to the grassroots.

The best way to scarify is to use a rake but if you have a very large lawn you may need to use a dethatcher[1] or a powered scarifier. 

Once you have finished these processes the lawn might appear slightly thin but by early spring it will look very healthy.

When a Fork is Not Enough to Aerate Your Lawn

When a Fork is Not Enough to Aerate Your Lawn

A fork may be all that is required for many small-size domestic lawns but with larger lawns, a fork just won’t do the job and specialized aerating tool. These can vary from manual devices that resemble forks but have a larger diameter and or longer tines, to push spike aerators or tow aerators.

If your soil is made from heavy clay then you might have to look at slicing aerators with rotating blades or use plug aeration as opposed to spike which will remove small cores of soil from the ground as it travels across the lawn.

What is Core/Plug Aeration?

Core aeration is a process that uses hollow tines to remove cores of soil, thatch, and grass from the surface of the lawn. The goals of core aeration are the same as those of spike aeration which are to allow the grass roots to access nutrients more easily, provide better water penetration, are circulation, and minimize compaction.

Because a plug aerator removes soil cores, rather than puncturing the surface of the ground, the process tends to have a much longer-lasting benefit. This means you are like to need to aerate as frequently. In addition, where the soil is severely compacted, or the ground is made from heavy clay, spike aeration may not be sufficient to relieve the problem and core aeration would be the solution.

Core aeration is carried out by using a plug aerator, these can be small machines that you push by hand to larger ride-on machines that can cover large areas quickly. Because of this, the efficiency of your watering and fertilizer will increase, which will ultimately result in healthier grass.

When you’re using an aerator machine, work over the grass in the same manner as you would while mowing; move in two different directions each time. In the summer, pay special attention to areas where children often play or where garden furniture is located. You will probably have to make several passes over the regions with the most compaction in order to get the best results.

The plugs that the aerators dig out should be left on the surface where they will gradually decompose back into the lawn’s soil.

When to Aerate Your Lawn

Generally, the best time to aerate your lawn would be in the fall, although this isn’t always the case and should depend on whether you have warm or cool-season grass. The reason that fall is often preferred is it should ensure that it will be responsive to your efforts and allow the ground to recover from the process. When the grass is dormant, it is not recommended that you aerate it.

For warm-season grasses, in the southern states of the United States, this isn’t always the fall and it is often better to aerate in the late spring/early summer, therefore include aeration in your spring lawn care checklist in these areas.

What to Do After Aeration

After you’ve finished aerating your grass, let soil plugs or leftover dirt dry where they fall to avoid a weed infestation. They’ll break down in the rain or crumble when you next mow your lawn, bringing healthy soil and organic matter to the surface of your grass.

It is ideal to overseed and fertilize your lawn immediately after aeration, as well as to do minor grass repairs. Where your aerator has made direct contact with the soil it will allow seeds and nutrients to reach deep down into the soil directly, while roots will have new paths for the nutrients they need. When used together, it may assist in getting your lawn to look amazing quickly with good seed establishment and thicker, more lush grass growth.

By including aeration on your yearly to-do list or doing frequent compaction tests to see if aeration is necessary, you can help make sure that your grass achieves its maximum thickness, health, and aesthetic potential.

When there shouldn’t be holes in your lawn


  1. University of California, Agriculture and Natural Resources: When to dethatch?