Scarifier vs. Aerator: Which Does Your Lawn Need to Thrive?

If you consider your lawn your pride and joy, you probably know there’s more to the game than mowing. Both aerators and scarifiers can make a big difference when it comes to keeping your grass strong, green, and happy—but what’s the difference between these two tools?

An aerator, as its name suggests, penetrates into your soil to help bring air, moisture, and nutrients to your grassroots. Scarifiers, on the other hand, stay closer to the surface, working to remove the thatch that builds up between the growing surface of the grass and the soil below. Both are important components of a healthy lawn maintenance regime. Read on for more important details on scarifiers vs. aerators.

Aerator vs. Scarifier: What’s the Difference?

As mentioned, an aerator is a tool that’s used to aerate—i.e., poke holes in—your lawn, while a scarifier is a tool that’s used to scarify—remove thatch from—your lawn.

Given the differences in their functions, these tools have different components in order to best perform their jobs.

In order to truly understand the differences between these tools, we need to take a closer look at the specific functions they’re performing.

Scarifier vs. Aerator: Differences in Function

Aerators and scarifiers are similar pieces of equipment in many ways, but they perform very different functions.

Aeration

Lawn aeration is an important process that sounds a little silly at first. Basically, it means poking holes into the soil to help bring more air (and all the good things that come with it) under the surface. 

Aerating your lawn combats the effects of soil compaction—which occurs when the dirt gets pressed harder and harder together over time thanks to factors like foot traffic. Plants can’t root well into tightly compacted soil, so aerating helps loosen it up, along with bringing light, oxygen, and nutrients to the roots of the grass.

Scarifying

Scarifying is more about what’s happening at the surface of the soil than below it. Between the live, green shoots that create the blanket of your lawn and the top of the soil that supports them, a layer of mostly dead plant material called thatch can build up. (Scarifiers are also sometimes called dethatchers.)

This is a natural process, and a little bit of thatch can even be good for a lawn, acting as a layer of insulation. Too much thatch, however, can suffocate your grassroots or trap water and rot. That’s why removing thatch from time to time is a helpful practice in cultivating a strong, healthy lawn—just as aerating is.

Differences in Operation

Both aerators and scarifiers are available in a variety of different types and styles, each suited to specific needs and budget availability.

Manual

Manual aerators and scarifiers are those that are used by hand. They may be a type that you need to physically stamp into the earth, resembling a pitchfork, or one that can be pulled behind you or walked ahead, similar to a mechanical lawn mower. There are even aerator shoes, which are spiked attachments that strap onto the bottom of your shoes, making aerating your lawn as simple as walking across it.

Before we move on, it’s important to understand that there are two different types of aerators, specifically: Spike aerators and core aerators.

• Spike aerators are fitted with tines that press holes into the surface of the soil.

• Core aerators use hollowed-out cores to remove plugs of soil from beneath the grass, and are often considered a more efficient form of aerating. The cores can be allowed to disintegrate back into the soil beneath your lawn.

Scarifiers use blades, instead, to do the work of clearing thatch from under the surface of the grass. Keep in mind that most manual scarifiers do not have a collection box, so you’ll need to physically gather the scarified thatch afterward to dispose of it.

Motorized

Aerators and scarifiers are also available in a motorized form, which looks a lot like a lawn mower with an engine. These are more expensive than manual equipment, and in the case of motorized core aerators, costs can top several thousand dollars. However, they’re a lot easier to use and more efficient than manual versions.

Liquid

Both liquid aerators and liquid dethatchers are available: chemicals that can do some of the work of these mechanical tools. However, they tend not to work as well as physical aeration or dethatching, and may require several applications to perform at all, nullifying any cash savings they might offer. 

Cost Differences

While both manual scarifiers and aerators can be purchased at affordable prices, they are also both available in more expensive motorized versions. Still, motorized aerators are more expensive overall.

For example, a manual scarifier can be purchased for about $50, and certain types of manual aerators can be purchased for as little as $30. A motorized scarifier or dethatcher, however, can be purchased for about $150, while some types of motorized aerators cost several thousand dollars. (Both types of devices can also be rented, but given their very high price, aerators may make more sense to rent while scarifiers may make more sense to purchase.)

Scarify vs. Aerate: Which Should You Do First—and When?

Both aerating and scarifying your lawn can be incorporated into your overall maintenance scheme. Gardeners have different opinions about which should be done first, but many suggest scarifying before aerating and giving your lawn a couple of days of rest between these two operations to give the grass time to recover.

Many lawn experts recommend scarifying your lawn at least once or twice a year—whereas, depending on the type of grass and soil you have (and how much foot traffic your yard sees), you may only need to aerate every one to three years.

Neither scarifying nor aeration should be done during your lawn’s dormancy period, as the grass will have little chance to recover after being injured in the process of aeration or scarifying. It depends slightly on the type of grass you have, but generally speaking, dethatching can be done in late spring and early fall, while it’s still relatively warm out. If you’re wondering when to aerate, experts suggest late summer or early fall.

If you need help while tackling this job, your local lawn specialist will be happy to aerate and scarify your lawn so you can simply kick back, relax, and enjoy watching the grass grow—literally.