Lawn aeration plays an important role in improving the flow of water, nutrients, and air to the grassroots. The surface of the soil is perforated with small holes to improve the health and vitality of the lawn. There are many types of lawn aerators and they each have their own advantages and disadvantages.
In this article, we will take a closer look at the aeration process and how the different types of aerators work.
The Basics of Lawn Aeration:

There are nine main reasons to aerate a lawn:
Improving Water Absorption:
When soil is compacted the water infiltration is diminished causing the water to run over the surface rather than penetrating to reach the grassroots. During aeration, soil openings are created to give the water a route to reach the root zone to promote moisture retention.
Alleviating Soil Compaction:
The soil under a lawn can become compacted over time and this prevents the efficient distribution of water, air, and nutrients. This affects the turf and rot health and aeration can create the channels for these elements to reach into the soil.
Improving Nutrient Uptake:
Any nutrients, including fertilizers in the soil, may be less effective if they cannot move efficiently through the soil. Aeration makes the uptake of nutrients more readily available to improve the health of the lawn.
Increasing Oxygen:
The grass roots need oxygen to breathe and compacted soil can diminish the oxygen in the root zone. Aeration provides an easy vector for oxygen to reach the roots to improve the overall health of the grass.
Stimulating Root Growth:
The roots can penetrate and grow freely in loose soil. A deep and extensive root system will make a lawn more resistant to disease, stress, and changes in the environment.
Increasing Microbial Activity:
During aeration, the soil microorganisms that decompose organic matter and thatch become more active which is beneficial for the soil structure.
Denser Turf:
Aeration encourages health and vigorous growth which improves the turf density for thick and luscious grass surfaces.
Reducing Thatch:
The layer of dead roots, grass, and organic debris that can form at the surface of the soil is known as thatch. When the thatch layer is too dense it can prevent air, water, and nutrients from penetrating into the soil. This can create ideal conditions for harmful pests and diseases which may damage the lawn. During aeration, the thatch layer can be broken apart to ensure that efficient decomposition occurs.
Preventing Erosion and Runoff:
The lawn becomes more sustainable when erosion and runoff are prevented with aeration.
The Best Time to Aerate the Soil
This is during the growing season because the grass can recover rapidly. But, there may be some variation depending on the type of grass you have and the local climate conditions. During lawn aeration, holes are created in the surface of the soil to improve the health and resiliency of the lawn.
There are many types of lawn aerators on the market, but they can be divided into three broad categories: spike, plug/core, and liquid aerators. These are available as manual and powered models and we will explore them in more detail below.
Spike Aerators:

A spike aerator creates holes in the soil using prongs or spikes to create openings for water, air, and nutrients to reach the grassroots. These machines are a frame with attached solid or hollow spikes or a series of hollow tubes positioned on a drum or roller.
The aerator is pulled or pushed over a lawn and the spikes penetrate to the desired depth. No machine is perfect, let’s take a look at the pros and cons of spike aerators:
Pros:
- Speed: Spike aeration is fast, this is a real advantage for people who need to aerate a larger lawn.
- Less Disruption: A spike aerator is less intrusive than a plug/core aerator that removes soil plugs.
- Easy to Use: A spike aerator is light and easier to use.
- Cost: Spike aerators are simpler machines and they tend to be less expensive than plug/core aerators.
Cons:
- Soil Surface Disruption: A spike aerator will disturb the soil surface, but it is less intrusive than a plug/core alternative. But, if a lawn has a well established thatch layer, spike aeration may not be the best approach.
- Soil Compaction: A spike aerator may provide some compaction relief, but not as much as a plug/core aerator, and some compaction around the holes it makes may occur.
- Long-Term Benefits: There may be limited long-term benefits because spike aeration holes can close quickly which reduces the efficacy over time.
Plug/Core Aerators:
A plug/core aerator is more likely to be referred to as an aeration machine or a core aerator. They have a different approach, these machines remove cylindrical soil and thatch plugs from the lawn to improve the overall health of the root system. These machines have a frame and chassis that supports coring blades or hollow tines. The plugs that are removed from the soil can vary in size but they tend to be 2-4 inches long. As the aerator is moved over the lawn, the tines penetrate the surface and the plugs are removed automatically.
Let’s take a look at the pros and cons of this aeration type in more detail:
Pros:
- Microbial Activity Increases: The soil is more exposed after core/plug aeration which encourages the beneficial microorganisms to break down the organic matter.
- Soil Impaction Relief: The removal of soil plugs reduces soil impaction, soil expansion will create conditions where the grassroots can easily grow,
- Improved Nutrient Uptake: During core aeration, the route for nutrients to penetrate down to the root zone is opened up to promote healthy grass growth.
- Reducing Thatch: The extraction of soil plugs will remove thatch that may prevent the water and nutrients from reaching the root zone.
- Long-Term Benefits: This type of aeration creates holes that are open for longer to promote air, nutrients, and water movement.
Cons:
- A Time Consuming Process: Core/plug aeration takes longer and this is especially noticeable when a larger lawn is aerated.
- More Disruption: This type of aeration is more disruptive and the lawn appearance can be degraded until the soil plugs are broken apart by mowing or they decompose.
- Aerator Size: These aerators are larger and heavier and they can cause soil compaction in turning and stopping areas.
Liquid Aerators:
Liquid soil aerators may be referred to as soil conditioners and they are designed to solve the same problems as a spike or core/plug aerator. A liquid aerator works differently, they are a spray on solution that changes the soil properties to make the surface more porous. There are four typical components found in liquid aeration products:
- Calcium and Magnesium: These are nutrients that promote soil flocculation (large soil clump) formations that improve aeration and drainage.
- Fulvic and Humic Acids: There are organic compounds that create soil aggregates (soil particle clusters) that form pore spaces to promote air exchange, water movement, and root zone penetration.
- Surfactants: These compounds reduce surface water tension to improve water infiltration to improve the soil structure and break apart compacted soil.
- Amino Acids: Some liquid aerator products contain amino acids that stimulate helpful microbes that break down organic matter and improve the soil structure.
Like the two mechanical aerators, there are pros and cons to consider before you choose a liquid aerator:
Pros:
- Easy Application: The products are applied with a watering can or sprayer and they are easy to use where mechanical aerators are not a practical option.
- Continuous Applications: Repeated intrusive aeration is inadvisable, but liquid aerators can be applied multiple times throughout the growing season to improve the soil.
- Less Intrusive: Liquid aerators do not disrupt the lawn which makes them an excellent alternative for people who don’t want plugs or holes in their lawns.
- Excellent Coverage: These products can cover areas that may be harder to access with other aerators.
- Fast Results: Many liquid aerators work fast, and there can be improvements shortly after the application.
Cons:

- Variable Effectiveness: The results may be variable depending on the soil type and other factors and there is less compaction relief in comparison to mechanical aeration.
- Soil Depth Penetration: A liquid aerator will not penetrate deeply into the soil which can limit the efficacy.
- A Temporary Solution: The effects may be temporary and additional applications are required to maintain any improvements made to the soil.
Manual vs. Powered Aerators:
The choice between a powered or manual aerator will depend on a number of factors, including:
- Lawn Size: A manual aerator should suffice for smaller lawns, but a powered model is a better option for large lawns.
- Time Constraints: A powered aerator is faster than a manual model.
- Aeration Depth: A powered aerator provides more effective deep soil compaction relief.
- Physical Effort: A manual aerator will require some physical effort to use and for some users, their strength and stamina may be a deciding factor.
- Budget: A manual aerator is more affordable, but powered models are more efficient if you need to aerate larger lawns.
As you can see, the choice between a powered and manual aerator will depend on your needs.
No powered or manual machine is perfect, aerators are no exception and it’s important to understand the pros and cons.
Powered Aerators
Pros:
- Easy to Use: A powered aerator can cover a large area with minimal physical effort.
- Extra Features: Many machines offer extra features, including spike and core/plug aeration attachments, variable aeration depth, and more.
- Consistent Aeration Depth: Due to their automatic nature the aeration depth is consistent across the entire lawn area.
- Improved Soil Penetration: A powered model has deeper penetration for improved soil compaction relief.
Cons:
- Maintenance Requirements: Powered aerators have moving components that require regular maintenance.
- Size and Weight: These are bulkier and heavier than manual aerators which makes them hard to use and store in tight spaces.
- Noise Levels: These can be noisy machines that may disturb neighbors.
- Price: These machines are more expensive to hire or purchase than manual aerators.
Manual Aerators
Pros:
- Light and Portable: Manual aerators are lightweight, easy to move and store.
- Quiet: A manual aerator creates no noise which makes them an ideal option for quiet operation.
- Minimal Maintenance Requirements: There are fewer moving mechanical components which significantly reduces the maintenance requirements.
- No Power: These aerators run on mechanical pushing or pulling power so operators don’t need to worry about fueling and trailing power cords.
- Cost: A manual aerator usually costs less than powered models.
Cons:
- Shallow Aeration Depth: A manual model may not penetrate the soil as deeply as a powered model and the aeration depth is determined by the strength and stamina of the operator.
- Aeration Speed: A manual aerator is slower to use and this can become a tiresome and time-consuming process on larger lawns.
When to Aerate Your Lawn:

The effectiveness of lawn aeration can be affected by the type of grass (warm-season or cool-season), the climate, and the overall health of the grass. There is no one-size-fits-all solution, but the following advice for warm-season and cool-season grasses should help:
Warm-season grasses include Bermuda Grass, St. Augustine Grass, Zoysia Grass, and others. These grasses can be aerated during the May to June active growing season. This gives the grass a chance to recover quickly and continue to grow after aeration. In early fall from late August to September aeration is still possible because the lawn can recover before the cold temperatures arrive.
Cool-season grasses include Fescue, Kentucky Bluegrass, Ryegrass, and others. The best time to aerate these grasses is early fall from late August up to September. The soil will still be warm, grass growth is continuing and the slightly cooler temperatures reduce the stress. The lawn can be aerated in spring if aeration doesn’t occur in the fall. But, when the grass is growing the soil plugs may not break down quickly and there could be visible holes in the surface.
3 General Aeration Tips
- If the weather is hot or there are drought conditions there will be extra stress on the grass which may damage the grass.
- Aeration should occur before over-seeding because the extra holes will help the seeds to establish.
- The soil should not be too wet prior to aeration because this can compact the soil.
Conclusion: Nurturing Your Lawn’s Health:
We hope that this overview of the various types of lawn aerators will help you to make informed choices for your lawn. Aeration offers significant benefits for lawns that have poor penetration down to the root zone for air, water, and nutrients. Choosing between a manual or powered aerator will largely be determined by the size of your lawn and your available budget. For most people, a manual spike or core/plug model will suffice or if you’re concerned about soil compaction you can explore liquid aeration methods. If you include aeration in your annual lawn care routine you should notice some positive changes.