Lawn aeration makes sure your grass gets adequate water and nutrients as well as loose soil for proper development of roots. But when it comes to core aeration, should you use a spike aerator or a plug aerator?
A spike aerator has sharp tines that penetrate the ground to make holes and aerate your lawn while a plug aerator has hollow tines that penetrate the core and pull out plugs of soil. Spark aeration is suitable for small lawns with mild compaction while plug aeration is good for fixing severe soil compaction and on large areas.
If you plug-aerated your lawn in the last season and have not run a heavy lawn roller on it since you may not need to do it again until after a few seasons. If you feel the need to do so, you might want to consider using a spike aerator instead.
Spike vs Plug Aerator – Differences
Here’s a quick table showing the differences between spike and aerators.
Spike aerators have sharp spikes that penetrate into the ground.
Plug aerators have hollow tines that remove plugs of thatch when pushed into the ground.
Provides short term soil decompaction since no soil is removed.
Provides long-term decompaction because plugs of soil are removed from the core to create air spaces.
Mostly manual spike aerators are available and suitable for getting rid of soil compaction on small yards.
Mostly mechanical plug aerators are available and suitable for small, medium, and large areas of yard soil decompaction.
As you can see from the differences above, you may want to use a spark aerator if you have a small yard. It is also a suitable choice when you want to get rid of minor thatch that’s causing compaction.
Plug aerators are mostly mechanical, unlike spike aerators that are mostly manual (except for the ones you hook on your lawn mower). In this sense, using a plug aerator is one of the best ways to ease soil compaction because the plugs are removed from the core to make the soil loose.
A spike aerator makes holes into the ground to make the soil loose. Unlike plug aerators, spike aerators do not remove any soil from the ground. They only poke holes in the ground to get rid of compaction.
Spike aeration is great, but it gets rid of soil compaction on a short term basis. Instead of removing soil plugs from the core of your lawn, the aerator’s sharp tines pushes soil down and to the sides.
Some mechanical spike aerators are curved and can provide very deep penetration – sometimes up to 9 inches deep without causing the mess of plugs on your grass.
Does spike aeration work?
Spike aeration works but provides short-term results because when you push the aerator into the soil, it pushes soil down and to the sides instead of removing the thick thatch that is causing compaction. With time, the soil will readjust and close the small holes you made in the ground.
The little holes do not reduce core compaction but they actually increase compaction deep in the ground.
Spiked lawn aerator shoes are way slow at the job. You can imagine spike aerating a 1000 square-foot lawn using aeration shoes. It will take you a lot of energy and time to complete the task.
How often should I spike aerate my lawn?
It is best to spike-aerate your lawn 2-3 times every season because the results do not last long. However, if you used a plug aerator even once in the last two seasons, you may need to spike-aerate just once a season to get rid of minor compaction problems.
Always test the thickness of thatch in your lawn two times each season to determine if it is too thick and causing compaction. If it is too thick, you may need to rent a mechanical aerator and dethatcher to help you get rid of the problem.
Types of Spike Aerators
Lawns that are not badly compacted can be fixed with a spike aerator. Depending on the size of your lawn, you can choose from a variety of them, including the following:
Spiked lawn aeration shoes are made of narrow, sharp spikes protruding from the sole. You can use them to aerate a fairly small yard just by walking all over it.
The spikes are usually thin enough to reduce the resistance you’ll get when pushing them into the ground. You may need to leave your oscillating sprinkler watering your lawn for some time to make it easy when you start aerating with these shoes.
You may need a heavy lawn aerator machine, but it is also a great idea to buy a good pair of spiked shoes for a lighter job once in a while.
Hand and foot manual aerators
These are the type you hold with your hand to place them upright on the lawn, and then step on to push the tines down into the soil to aerate.
While I recommend hand-and-foot manual spike aerators, I find them to be time consuming and a little energy-intensive to use. You’ll be exhausted if you have a large area to aerate.
On the good side, manual aerators are pretty much cheap and easy to use, so you can have one for lighter aeration lawn maintenance.
Mower wheel spikes
You’ll not find these ones common, but they exist. They are accessories added to the wheel of self-propelled lawn mower so that you can aerate the core of your lawn while mowing.
The downside of these spikes is that they are small and may not really make deep holes. A lawn that is badly compacted, wheel tines may not be able decompact it properly.
Push spike aerator
Push aerators are circular just like lawn rollers except that they have spikes all over them. As you push them, the spikes make holes in the lawn, decompacting the core.
Since you’re the one pushing the aerator, you really want to prepare the ground by watering it deep enough to make it soft, otherwise the task of pushing the aerator to loosen up the soil will be tough.
A plug aerator is much different from a spike one because it removes plugs of thatch from the ground. This makes it a very effective tool for relieving soil compaction for the long-term.
How does a plug aerator work?
Plug aerators have hollow tines that remove about an inch of thatch from the core when pushed into the ground, making it well aerated. They are much more effective at getting rid of soil compaction even in yards with clay soil, and the effects are long-term compared to those of spike aeration.
Some of the best plug aerators are mechanical. Here’s how they relieve core compaction:
- Plug aeration machines have hollow tines that rotate while rolling on the lawn.
- The tines remove cores of soil that are about an inch long and about a dime’s diameter.
- Plug aerators are much more successful at loosening up compacted soil and getting rid of the compaction.
How deep should core aeration plugs be?
For the best results, plug aerator tines should make holes 1-6 inches deep into the ground and remove plugs that are about 0.5-0.75 inches wide. Mechanical core aerators are great for long-term aeration because they remove plugs up to 6 inches apart, making your lawn soil loosen up significantly.
The problem with most plug aerators is that they are commercial machines. However, I bought one for my own home use, and it does a great job.
Should I pick up plugs after aerating?
You don’t need to pick up the plugs after core aeration because they’re usually a thick mass of decomposing thatch with a lot of nutrients. You can leave them on the lawn to break down and release nutrients into the soil and feed the grass.
However, if you don’t like their appearance, you can rake and add them to your compost. Once fully decomposed, you can use it for topdressing areas where you need to overseed the lawn, or even for growing new sod.
Can aeration be too much?
Since plug aerators are so effective at decompacting soil in the yard, I recommend you use them just once a season, or even once after every few seasons unless your soil type is really compacted.
Lawns established in clay soil are the most problematic when it comes to compaction, so, core-aeration about two times a season will ensure you maintain a healthy lawn. In clay soil, use a plug aerator instead of a spike aerator.
If your grass is thick and full such as Bermuda grass, you may need to aerate a little more often because this type of grass can quickly form a layer of thick thatch really fast especially if you don’t dethatch quite often.
- Virginia Cooperative Extension: Aerating Your Lawn