It’s mid-February as I write this article and most of the Northern Hemisphere is currently blanketed in snow. While shoveling snow, many homeowners are fondly remembering the lush green grass of summer. Well, with spring just around the corner, it’s time to begin thinking of lawn care.
Soon, we will be fertilizing, watering, and mowing our lawns once more. But an important step in springtime lawn maintenance is often missed. It’s vital to aerate the lawn in order to promote healthy growth.
We’ll cover the basics of aeration – what it is, and why it’s so important – and discuss what to look for in a lawn aerator. We’ll also review some of the best products currently on the market.
What is lawn aeration?
Over time, lawns become compacted as foot traffic compresses the soil. Dried and matted grass left over from the autumn makes the soil dense and prevents air, nutrients, and water from reaching the roots of the lawn.
Aerating the soil alleviates this problem – punching small holes into the ground allows the roots better access to these key resources.
Aerating a compacted lawn will improve the soil drainage, control lawn thatch, reduce the level of compaction, and help the grass roots multiply while also encouraging worms, and other helpful microflora and fauna.
What is lawn thatch?
The thin layer of dead roots, stems, and cells from grass that have fallen into the soil is called thatch.
It’s a barrier layer between the healthy, growing grass and the soil – and when less than ½” thick, it can help protect the roots from the damaging effects of the harsh midday sun.
If the thatch becomes too thick though, it can prevent the shallow grass roots from solidly establishing themselves in soil, and they will instead anchor into the nutrient-poor thatch.
Dethatch or aerate?
Most homeowners dethatch their lawns at least once a year, by vigorously raking up fallen leaves, or using a rake to dig deeply into the grass as part of the spring cleanup. This method works best if the thatch buildup is minimal.
When the thatch layer exceeds ½”, aeration may be the better solution for promoting healthy lawn growth.
While not all lawns require aeration, there are several cases where it’s extremely beneficial:
- If your home was newly built, the construction process (heavy equipment, lots of foot traffic) will have severely compacted the lawn
- If your yard is used often and children or pets are routinely running over the grass, it’s likely that the soil is compacted
- If you’ve recently laid down sod, there may be a mismatch in soil density between the sod and the existing soil and aeration will blend the layers together, helping the roots establish themselves
- If in doubt as to whether aeration is really necessary, Virginia Tech recommends removing a square foot section of the lawn at least 6” deep. If the grass roots extend only 1”-2” into the ground, the soil is probably compacted and would benefit from aeration.
Best time to aerate
Generally, this should be done when the grass is growing the fastest. This allows the roots sufficient time to multiply and re-establish themselves in new soil. For cool-season grasses, this happens in early spring while for warm-season grasses, you should aerate later in the spring.
It’s a good idea to aerate the lawn annually, and if it gets very heavy use, it might be helpful to aerate twice per year.
Types of aerators
There are two types of lawn aerators: spike and core/plug aerators.
- The spike aerator uses wedge-shaped solid spikes to push the soil sideways as it punches holes in the lawn.
- Because no soil is removed from the ground, the compacted earth can easily expand when wet and the holes will close.
- The benefits of lawn aeration are slightly offset by the compaction occurring around the sides of the holes left by spike aerators as they push into the soil.
- Spike aeration is most effective on sandy or loamy soils.
Core or plug aerator
- The core aerator removes a plug of soil from the ground and leaves it on the turf surface.
- The holes can remain open for a long time, which allows air, water, and fertilizers to reach the grass roots. This improves the long-term health of the lawn but puts stress on the grass over the short term.
- The best time to use a core aerator is when the soil is moist but not saturated with water. If the soil is too dry, it will crumble inside the tines rather than pop free as a soil plug.
- If the soil is too wet it may stick inside the tines, again preventing the aerator from removing the soil which may also cause the spikes to compact the soil instead of loosening it.
- Core aeration is best suited to heavily compacted or heavy clay soils.
Powered aerator vs. manual aerator
A powered aerator uses the power from ground propulsion to drive its multiple tines into the soil. These machines allow the lawn to be aerated in approximately the same time needed for mowing.
A manual aerator usually has 2-5 hollow tines mounted on a step bar. When the operator steps downward, the tines are forced into the soil; when they pull the handle upward, the cores are removed from the ground.
Manual aerators are less expensive but more time-consuming than powered ones. If the tines become clogged with soil, the process is slowed down even more.
Best lawn aerator for the money
Weight tray that can hold up to an additional 140 lbs. allowing for increased tine penetration into the soil
Excellent for high-traffic areas such as playgrounds and sports fields or drought-damaged lawns
Fitted with a simple-to-use cantilever transport handle for easy raising and lowering of the tines
Durable 10” flat-proof tires for smooth transport with little to no maintenance
For homeowners with large lawns and power mowers or ATVs, this unit is an excellent choice. At around $200 USD, this aerator will easily pay for itself in rental cost savings.
The 48” wide axle with 8 spools and 32 galvanized plug aerator knives make quick work of even larger properties or parkland. The tines are extremely sharp and durable even through extensive use.
The weight tray allows the operator to apply extra pressure to more heavily compacted areas, ensuring that adequate plugs are removed.
The only downside is that the assembly is time-consuming and can sometimes be difficult as the knives are extremely sharp – it’s best to wear heavy-duty work gloves during assembly. Also, there is no means of securing the added weight to the frame, and the lip on the tray is low, so an unsecured load may tumble off.
Removes two soil plugs ½” in diameter and up to 3½” in length
Durable powder-coated steel construction
Designed to reduce back strain with a foot bar for extra leverage and a 37” length
Good value for a small lawn
This manual core aerator is an excellent choice for small projects or spot treatments – it is well-built and sturdy.
It’s easy to use and, once a rhythm is established, a large section of lawn can be aerated in a few hours.
It’s best to ensure that the lawn is quite moist before beginning as the tines will clog up if the soil is too dry. Several users reported that the coring tines clog regularly and recommended either carrying a spike or screwdriver or preparing a bucket of water to soak the coring tips if they get clogged.
Comes fully assembled and ready to use with an instructional video
Lightweight and easy to walk in and use
A space-saving choice for smaller gardens as they’re compact and easily stored
Weather-proof metal parts
These spike aerator shoes are an excellent choice for homeowners with sandy soil.
There is a small learning curve in order to walk without the spikes sticking in the ground, but the included video demonstrates the proper technique.
The shoes are easy to adjust and are comfortable and lightweight enough to wear while handling other outdoor tasks.
The 2” spikes are quite narrow, so the holes may close back up if the soil gets wet soon after use.
Single-pin universal hitch is compatible with lawn tractors, ride-on ZTRs, and most ATVs
Fully-enclosed weight tray that holds up to 150 lbs
24 heat-treated, 16 gauge steel plugging spoons with sharpened ends for easier penetration to remove soil plugs up to 3” long
Easy-to-reach transport lever engages the 10” Never-flat rubber tread tires
This aerator is well-designed and very durable with high-quality parts. The smaller size makes it easy to transport and to store – and at 65 lbs it is light enough to be stored hanging on a wall.
At around $200 USD, this machine provides an excellent value for the price especially given that it’s manufactured entirely in the United States.
Though the assembly instructions can be confusing, it was relatively quick and easy to assemble.
Some buyers reported missing or damaged parts, they also stated that Brinly’s customer service team was happy to ship out replacement parts immediately
5 extra strong welded tines set in the bottom bar
Designed so that the soil plug are ejected from the top of the hollow tines
Ideal for small lawns or spot treatments of high-traffic areas
This 5-tine manual core aerator is built to last and is excellent for small lawns or patches that are heavily compacted.
It is lightweight and easily stored, but sadly does not always perform as well as expected.
Unless the soil is quite wet, it’s rather difficult to force the tines into the ground, which slows the aerating process considerably. Also, the tines clog and the plugs do not always eject automatically.
This aerator might be easier to use with a 3- or 4-prong design.