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The Lawn Review: Home » Lawn Aerator vs Dethatcher vs Scarifier: Guide To Using Each

Lawn Aerator vs Dethatcher vs Scarifier: Guide To Using Each

Lawn aerators, lawn dethatchers, and lawn scarifiers are all tools that can be used to help your yard thrive.

Grass in the fall

But these are all too commonly confused with each other. Some folks only aerate, others only dethatch, and hardly anyone only scarifies.

In reality, these are a holy trinity that when used together can absolutely amplify your lawn care results and get you the greenest grass in the Fall.

Curious? Let’s dig in.

Why we started this site

We started The Lawn Review out of frustration. We couldn’t find clarity around what type of products were actually good and reliable. All the fertilizers we tried didn’t work. We ended up with a dying lawn, wasted time, and wasted money.

review lawn tools
We take this stuff seriously!

So we started buying and reviewing lawn tools and figuring out which ones were the best. And now we’ve moved onto actually keeping that grass nice and healthy all year around. 

We’ve spent thousands of hours building this content for people just like you and me – normal people.

Lawn Aerators Explained

A vital part of taking care of your lawn is that it needs air and other nutrients to help it thrive. Over time, soil can become dense and nutritionally dead. Water can no longer reach it and neither can sun or other vital nutrients.

Aeration is the process of bringing air and soil turnover to your lawn. Most aerators are core aerators, which pull plugs of compact, older soil to the surface of your lawn. Removing these plugs (which look like dog turds) allows for water and other nutrients to reach deep down into your soil, bringing vitality and health to your entire yard.

lawn aerator core
A core aerator we rented from Home Depot

Lawn aerators tend to make your yard look like crap for a few weeks, but are often done in combination with some of the other tools we discuss today. Once these are used together with overseeding your lawn, you will start to see your lawn completely rejuvenate itself.

core aerator plug
Not dog turds

You can rent a lawn aerator from Home Depot for a pretty cheap price, among a ton of other things you can rent from Home Depot.

When to aerate your lawn

Most folks should aerate their lawn in the fall. If you have a cool or transition season grass, this is the perfect time to reset your lawn and allow for new growth. We recommend aerating after you have already scarfied and dethatched your lawn.

If you have warm season grass, spring is actually the best time to aerate – so for those in Florida and Texas, Spring is the time.

For a full guide, we wrote a longer document that highlights the best time to aerate and overseed your lawn.

Lawn Dethatchers Explained

Lawn dethatchers are some of the most satisfying lawn tools on the planet. It’s basically like  peeling the plastic off of a new appliance, but for your whole yard. 

Greenworks cordless dethatcher

Lawn dethatchers, particularly electric lawn dethatchers, work by using metal tines that pick up dead, old grass in your yard.

Thatch is the compilation of dead grass, roots, and weeds in your yard that forms a little blanket over your soil. It can be good for a few things, like keeping nutrients and retaining moisture, but if it gets to be too much it can totally choke your yard. 

thatch dethatching
This is thatch.

Lawn dethatchers differ from lawn aerators in that they don’t actually interact with the soil. Whereas core aerators pick up big chunks of dirt and put them on top of your grass, dethatchers simply pull up dead thatch and bring it to the surface. 

Sun Joe Dethatcher
A Sun Joe dethatcher we used.

We recommend using a dethatcher before a core aerator. Dethatching will give you a better aeration and allow for more nutrients and seed to get down into your soil.

Electric dethatcher recommendations

You can also dethatch your lawn with a manual dethatcher, but it is a back breaking process that will crush your hopes and dreams. 

Greenworks dethatcher tines

Electric dethatchers are amazing and there are some great options. We have reviewed the Greenworks dethatcher and the Sun Joe dethatcher and even compared the two in the same post. 

Scarifiers explained

Scarifiers can be thought of as an extension to your dethatcher. Scarifiers use little blades to cut vertical lines just at the surface of your soil. Why would you want that?

Well, you may want to help cut up some of the thatch before using the dethatcher and aerating. Scarifiers are not as necessary as dethatchers and aerators, but can definitely give you better results when you dethatch. 

scarifier blades
The scarifier blades that help shred thatch.

If you have never used a dethatcher and think your lawn is completely covered in thatch, then it’s worthwhile to use a scarifier to make sure the thatch is nice and loose. Otherwise, the dethatcher may only be able to get a small percentage of the thatch.

scarifier dethatcher aerator
The scarifier is a good tool in combo with the aerator and dethatcher.

Scarifier product recommendations

While I’m sure you could buy an electric scarifier, most electric dethatchers have a scarifier attachment that you can quickly run over the yard before dethatching.

The Sun Joe dethatcher we used in one of our videos had a nice scarifier attachment that easily popped on.

The Best Time to use a scarifier, dethatcher, and aerator

As mentioned previously, the best time to use a scarifier, a dethatcher, and an aerator is in combination with overseeding your lawn.

The actual order of events is:

  • Use a scarifier if needed to break up all the thatch in your lawn
  • Use a dethatcher to pull all the dead thatch out of your lawn
  • Then use an aerator to pull up compacted soil

Once you have done these three things, your lawn will be ready to overseed. For most folks, the best time to do this is around mid-September to early October. This gives the appropriate time for the cool season grass seeds to germinate and grow before the winter freeze comes.

For those with warm season grass, the best time to aerate and overseed is in March, following the exact same process.

The importance of overseeding your lawn

Overseeding your lawn is important for the health and vitality of your lawn, but is going to be a fruitless (or grassless) effort if you don’t dethatch and aerate your lawn. 

Overseeding your lawn is the best way to get luscious grass but also helps choke out weeds and other invasive grass types that can quickly overtake your yard.

Following overseeding, you want to be sure to be very consistent with a watering schedule. We recommend at least twice a week for 50 minutes in each area and preferably in the morning.

Frequently asked questions

What is the difference between a Dethatcher vs Aerator?

A dethatcher is used to take the top layer of dead grass, or thatch, off of the top of your yard. This prepares it well for further aeration, receiving more seeds and nutrients, and easier watering.

We made a cool Google Web Story highlighting the difference between aerators and dethatchers!

An aerator pulls little plugs of compact soil out of your lawn, allowing air to flow into the soil and restoring the vitality of the soil. Aeration is a necessary yearly investment in your lawn to help keep it lively and green.

What is the difference between a dethatcher vs a scarifier?

Dethatchers and scarifiers commonly go hand-in-hand and complement each other well. Scarifiers are used to cut up thatch, loosening it for the dethatching process.

Dethatchers are used to collect thatch from the top layer of your yard. Their performance is enhanced by scarifiers, especially if you haven’t dethatched in a long time.

Alex K

Alex K

Alex is not a lawn care natural. He had to learn things the hard way. But after stumbling through his first few seasons of lawn care, he learned a lot. Mostly - what not to do. Alex has become one of the country's advocates of battery-powered lawn tools, quoted in the Washington Post among other highly visible publications. Alex started The Lawn Review with his friend Tyler - who you may see in some of the videos on this website - to help normal people like you understand how to take care of their lawn themselves with the best tools possible. Alex has thousands of hours of experience using hundreds of different lawn tools and has found exactly what to look for in each type of tool. He speaks with deep experience not only about the boring technical specifications, but what the tool actually feels like when you are using it, what to look for before you make a purchase, and how the lawn tool measures up when you factor in price.