If you’re at all interested in lawn care, you’ve probably heard about the need to “dethatch” your lawn. While you can rent a dethatcher at your local hardware store, the Sun Joe Dethatcher and Scarifier is a simple and affordable solution that will allow you to dethatch and lightly aerate your lawn whenever you want. Whether you need to dig up some thatch to let your lawn breathe or scarify it to relieve soil compaction or improve seedlings, the Sun Joe is a fantastic addition to your home maintenance arsenal.
When I bought my house in 2018, I dove into the world of DIY lawn care - mainly because a septic system replacement left us with a giant mound of mud, weeds and nothing else.
Sun Joe is legendary in these online circles, because it has long been one of the few affordable products on the market that can replace the need to rent a bulky, professional-grade detergent. With a one-day rental often costing around $80, it can quickly become more economical to purchase your own device.
To see if the Sun Joe lived up to its reputation, I called it in and put it to the test on my lawn. I haven’t dethatched my lawn in about two years, and the soil is very compacted on the side of my yard, so the Sun Joe had its work cut out for it.
Stubble removal, scarification or aeration: What’s the difference?
What is dethatching? Dethatching is the mechanical removal of the layer of dead plant material that accumulates in most lawns like a carpet on the ground. While some thatch is good - it can act as a natural barrier to weeds and keep water from evaporating too quickly too much makes it difficult for seeds and fertilizers to contact the soil where they belong.
Scarifying is basically pure dethatching. Instead of scraping the surface with fine rake-like teeth, the Sun Joe’s scarifying head rolls blade-like arms over the ground to dig into the soil and pull out the thatch simultaneously. This method is much more disruptive to the top layer of your lawn, but it can help reduce soil compaction through light aeration.
Ever walk across a lawn that feels hard as concrete? It’s soil compaction that’s blaming. When the soil is too compacted, grass seed, fertilizer and water simply walk away. It takes more energy for the roots to grow and the grass to spread, and it prevents air from reaching the root layer. This is bad.
The best way to reduce soil compaction is to “aerate” your lawn, which involves using a machine that rolls over your lawn digging up tons of little plugs of dirt.
To find out if your lawn needs to be aerated, take a screwdriver and poke the soil. If it slides right in, all is well. If it doesn’t go in without forcing, it’s time to aerate, either with a scarifier or (if your problem is more severe) with a gas aerator.
Whether you need to dig up some thatch to let your lawn breathe or scarify it to reduce soil compaction or improve seeding, the Sun Joe is a fantastic addition to your home maintenance arsenal.
Basically, a scarifier like this Sun Joe is like an electric lawn mower, except instead of spinning a blade that cuts your grass, it spins a wheel that has two types of attachments: a scarifier that will effectively rake thatch from dead plants and a scarifier that will do that and also roll through your soil and more aggressively tear up the top layer of thatch and soil.
Like a lawn mower, the scarifier comes with a (tiny) collection bag, which prevents dead thatch from falling directly onto your lawn (if you so choose). Although replacing the heads requires loosening a few bolts, it’s a pretty simple machine overall.
Your primary concern is that it runs on a corded electric mower (which means you’ll need two 50-foot extension cords). This may seem like a pain if you’re used to gas-powered lawn care equipment, but unless you have a really enormous lawn, it will get the job done.
About the Sun Joe AJ801E Brushcutter and Scarifier
Power: 12 amp corded electric motor
Heads included: Cultivator, scarifier
Material: Alloy steel and plastic
Weight: 27 pounds
Self-propelled? Self-propelled : Yes
Cutting width: 13 inches
Dimensions: 24 x 20 x 12.5 inches
Starting Style: Push button instant start
What we like about the Sun Joe scarifier and dethatcher
In dethatching, the Sun Joe is really effective.
In my testing, I focused first on my front lawn, which was not affected by the septic tank replacement I mentioned earlier. It’s a fairly thick mix of perennial rye and tall fescue turf-type grass. In some low areas, it is prone to thatch, which can even cause my mower to have trouble.
In just two passes with the Sun Joe, I could remove an entire wheelbarrow of thatch from this one 600 square foot section. It was intense, and it also immediately highlighted the Sun Joe’s biggest problem: It removes far more thatch than you’d expect, and more than its small recovery bag can handle (more on that later).
The scarifying feature is dominant for seedlings
My side garden is in much better shape than the front or back. Removing the septic tank required many trucks and heavy equipment to pass over the lawn, which was not adequately raked and scarified at the end of the job.
To make matters worse, it replaced the lawn with a type of grass called “Kentucky 31”, which has a reputation for growing in ugly blades and clumping, leaving plenty of room for moss and weeds to take hold.
The result is an area that I’ve had to maintain over the past two years to keep the weeds from taking over. Over the course of three winters, the ground has continued to harden, to where I don’t even like walking on it barefoot and am afraid my kids will hurt themselves if they fall on it - and that’s after using the professional detergent to dig up some clogs.
While I’ll have to see how it performs over time, the Sun Joe immediately combed through that part of my lawn, roughing up the grass and disturbing the top layer of soil. The machine has five depth settings, but I found that the deepest one was the only one that really did the job.
I ended up going over that part of the lawn twice, the second time perpendicular to the first. The grass really looked like it had suffered, but there was a lot more loose, soft soil on top to plant seeds in.
An electric motor for minimal mess, maintenance and hassle.
While gas-powered lawn care equipment is more powerful, electric equipment has come a long way. The Sun Joe is proof of that, with performance comparable to the heavy, inconvenient professional dethatching machine I’ve rented in the past, although it’s much lighter, much easier to use and easily turned on without complex - and for some people, downright impossible - pulling operations.
The Sun Joe is also easier to store without having to make sure you drain or stabilize the remaining fuel before putting it away for a while. For a machine you’re probably going to use a few times a year and forget about, that’s a big plus.
What we don’t like about the Sun Joe brushcutter and scarifier
The price can be higher than a simple rental.
Prices vary depending on where you live, but around me, you can rent an aerator or detergent for $50-$80 a day. That’s certainly cheaper than the $160 to $200 you’ll pay for the Sun Joe (prices fluctuate depending on the retailer), although it should be noted that the Sun Joe is both a detergent and an aerator and those rental costs will usually get you one or the other.
Of course, these gas-powered tools, while heavy, are also much more powerful and are better suited if you have a lot of ground to cover, such as an entire soccer or baseball field. My property is only a quarter acre, and the Sun Joe made quick work of it. It could definitely handle an acre of lawn.
The collection bag is constantly filling up
I wouldn’t describe the thatch problems in my lawn as an emergency or anything, but the collection bag filled up after only one pass over 100 square feet. I have a standard walk-behind mower, and I usually have to empty the collection bag once halfway through the mowing. With this machine that only pulls thatch, I had to empty it probably 10 times in one pass on my lawn.
You can use it without the collection bag - most motorized dethatchers you’ll rent don’t have a collection bag at all - but then use a leaf blower to remove the dead plant material from your lawn (I also just ran the mower over some of this material to let the mower pick it up). I raked it all out, which took more time than the actual dethatching.
Either way, you’ll have to worry about a few extra steps. One person also used the bagless scarifier and her husband got a rock that hit him where the sun doesn’t shine, so be careful with that.
Switching from scarifier mode to dethatching mode requires extra tools.
This is not uncommon, but it can be unexpected: You’ll need a socket wrench to switch from scarifier to dethatching mode. It’s not a difficult operation - just remove a screw with an 8mm Allen wrench that holds the scarifier arms and replace it with the scarifier end - but if you don’t have an Allen wrench set, you’ll need to get one, or get one of the better starter tool kits we’ve tested that contains it.
The scarifier function doesn’t ventilate very well.
While the Sun Joe can compete with professional gas-powered scarifiers, I don’t think the scarifying function is up to par with a professional aerator. It really shreds the top layer of dirt, more than using a metal rake and doing it by hand, but it only goes so far.
A full aeration will dig down to 2 to 3 inches and pull out plugs of dirt. This is the only long-term solution I would trust to relieve severe compaction. I think the scarification feature of the Sun Joe is enough to improve grass over-seeding, since you don’t want the grass seed that deep in the soil anyway, but if you have severe compaction problems, consider renting a unit.
Should you buy it?
Absolutely, it’s the best value for anyone who regularly tends to their lawn.
Most people know the basics of lawn care: high-quality seed suited to the location, nutrient rich fertilizer, regular mowing, plenty of water and sunlight. But, if you want your lawn to thrive, you need to create the conditions that make it possible.
Dethatching and aeration (or in this case, scarification) are excellent ways to tackle the problems that inevitably arise in even the best-maintained lawns. If you commit to doing these things even once a year, the Sun Joe will pay for itself compared to renting other machines.
While it’s not as powerful as the gas-powered machines you rent from Home Depot or Lowe’s, it’s lighter, more convenient, more accessible, and it shreds extremely well. In fact, there was so much thatch on my lawn that it took me an extra 90 minutes to rake and dispose of it.
The “scarification” tool wasn’t as effective as a good heavy-duty aerator that pulls 3-inch plugs of soil out of the ground, but it was enough to temporarily relieve my lawn’s problems, and it should improve seed-to-soil contact, which is essential for overseeding and repairing your lawn.
Overall, anyone who wants a beautiful lawn will have to tackle thatch and aeration at some point, and this machine is one of the best, most affordable ways to do it on a DIY budget. It’s not a perfect machine, but there’s a reason it’s popular, and our testing shows it’s exactly as good as advertised.
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