Lawn aeration (enabling air to get into the ground) is a quick and effective way to improve the health of the grass within your lawn.
So how do you get the benefits of aeration without having to dig over your entire lawn? We have put together this article for all the tips and tricks you need to get an incredibly lush lawn.
What Is Lawn Aeration?
Lawn aeration is something that gardeners, greenkeepers and enthusiasts have done for years. Years ago your grandparents and parents would use their garden forks to push holes deep into the soil beneath their lawn. This helps rain, air and nutrients get down to where it is most needed (the root zone).
Greenkeepers would use machines to carry out the process. The machines would have metal tines (a piece of metal around 5 inches in length) attached to a shaft that spins. As it spins it pushes these tines into the ground as the machine runs across the lawn. There would be numerous tines on the shaft allowing for multiple holes to be pressed into the lawn in a matter of seconds.
The tines are either solid tines or hollow tines. The solid tines push holes in the ground, while hollow tines do the same but then pull out the core of soil from within the shaft. This benefits the lawn by relieving compaction too, as well as helping drainage within the soil structure.
Why Do I Need to Aerate My Lawn?
Any time you poke small holes into your lawn is an act of aeration. Aerating your lawn increases air circulation to the roots, as well as encouraging better water and nutrient uptake to increase the overall health of your lawn. Air circulation will limit the growth of any unwanted microbes and will allow fresh oxygen to permeate the ground and carbon dioxide escape.
Your lawn cannot do this process itself and regular aeration will reduce the extreme compact nature of lawn soil, preventing soil blocking the root system. A blocked root system cannot take up enough water and nutrients for your grass to healthily grow.
Aerating also helps break up the thatch layer – the layer of dead leaves, stems, and roots that build up between the soil and grass – that isn’t great for lawn health.
When Should I Aerate My Lawn?
You should aerate your lawn when the soil is at its most moist – this will either be in the spring or in the autumn. You need to aerate when the soil is moist as it will be much easier to poke holes when wet and cause less damage to your lawn. In winter, the soil of your lawn will be too hard to easily penetrate in general (However don’t discount a winter aeration if the ground is dry).
Spring is often the time people choose to aerate their lawn as it fits in nicely with the grass’ growing season and the other chores that need to be done in the garden in preparation for summer.
Aerating in Spring also gives the grass enough time to properly heal in time for Summer – the time of year when the grass does most of its growing and you sit out in it more!
Like all gardening, however, this is greatly dependent on the temperamental Great British weather. Do not aerate if Spring has been particularly wet as too much moisture in the soil will limit the air and moisture that the roots are exposed to before the soggy soil closes up any holes you have made.
Aeration Schedules
Autumn
If you choose to aerate in Autumn you should use a hollow tine aerator wherever possible. This will improve the draining capabilities of the soil and raise its temperature slightly. Keep in mind that this style of aeration should only be used when you are sure your lawn will have time to recover.
Begin the aeration process in the final days of August, or at the very latest early September, and continue through to the middle of October. Aerating during this time frame will prevent the lawn heaving up as it will not be exposed to frost – avoid this as far as you are able – and the weather is naturally moving from dry to wetter conditions.
Tining in the later months of the year when the weather is colder has the added benefit of stimulating root development. This will make sure that your lawn is looking its best in Spring and Summer the next year.
Spring
If you prefer aerating in the Spring, add a slitter to any aeration equipment for the best results. This will slice through roots, encouraging them to grow back further down into the soil and much thicker. This will help improve the health of your lawn and roots that are lower down will have access to more water come the hot and dry Summer months.
Any time from March to November
Between these months, it is best to begin spiking your lawn to a depth somewhere between 5cm and 15cm deep. You can do this with lawn aerating sandals, a rolling lawn aerator, or something as simple as a garden fork.
Be sure to repeat this process every few months but do not spike your lawn when the soil is wet or when it is too cold. If it is too cold and there is a frost coming or if the ground is too wet, your tools are just going to get stuck.
How Often Do I Spike My Lawn?
The frequency with which you spike your lawn will depend on the type of lawn you have. This will also dictate when you should spike your lawn.
If your lawn has hard or clay soil you need to aerate at least once a year. This is because the density and weight of the soil prevents air and water from getting to the roots, limiting water uptake from the grass and encouraging unwanted microbial growth.
A new lawn needs to be aerated several times a year as the root system needs a little help growing. You do need to wait at least six months before aerating a brand new lawn as the seedlings need time to get comfortable. Ideally you should aerate a new lawn once every six months after the initial six month maturity period.
If your lawn is not new or grown in clay or hard soil, aim to aerate once every one to three years. This will keep the lawn healthy without doing any damage.
You can always aerate more frequently if you notice that the lawn is looking a little less healthy between sessions, but do not aerate more than twice a year as this will do nothing other than tarnish the quality of the soil.
How Do I Aerate My Lawn?
To aerate your lawn you need to choose a day when the soil is sufficiently moist. This is ideally the day after a good amount of rainfall or the day after you have thoroughly watered it. Moist soil will make the whole process significantly easier.
You need to decide what tools you are going to use to aerate your lawn. The tool choice will be dictated by the type of soil you have and the size of the area you wish to cover. Lawn aerator shoes, for example, are good for small patches in need of aeration.
To use, simply attach to your gardening shoes and stomp around the grass, letting the spikes penetrate the soil. You can also use a hand aerating tool for small areas as they are cheap, effective, and dig out a hole to a specific depth. Similarly, a hollow tine aerator takes out a plug of soil which will prevent the hole sealing up too quickly.
Machine aerators can be used for larger patches or big lawns, with larger machines needing to be towed by a tractor. These are decidedly more expensive and, because they are machines and that much stronger than hand or foot operated aeration tools, can cause more damage to your lawn when not used properly.
Remember to make multiple passes over areas of your lawn that are very compacted. This is necessary as aeration equipment will not penetrate all of the soil in compacted areas with a single pass.
Keep in mind that not all areas of your lawn will need aerating at the same time – less compacted areas can easily be left for up to three years while harder parts of soil need to be done on an annual basis. You only need to aerate the areas of lawn that need it so save softer sections for the next year.
Apply fertiliser after you have aerated as this will replenish any lost nutrients and help your grass thrive. This often results in a much more lush, thick green lawn which will benefit further from regular mowing.