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Thatch- a tightly bound layer of living and dead plant material that forms between the grass and the soil- tends to build up slowly but surely.
Interestingly, while it can hinder proper growth by preventing air and vital nutrients from reaching the roots, thatch is not all that bad.
In fact, a thin layer of thatch is not only normal for the most common grass species but also hugely beneficial for your lawn- it slows water loss, maintains helpful microbial activity, protects your grass from foot traffic, keeps soil cool, and more.
In short, you should not always dethatch your lawn whenever you have a thatch issue.
We will discuss the pros and cons of dethatching lawn in this article to help you make an informed decision.
Pros and cons of dethatching lawn – what you should know
The first question we have to address is: Does thatch really pose a big problem for our lawn?
But there’s a caveat: Not all the time.
Listen to this crucial fact… thatch will only impede the health of your turf if it has formed excessively.
So what does that mean? It simply means that you should only be concerned about thatch buildup if it’s ½” thick (or more).
Because too much thatch is impermeable and will restrict all nutrients and moisture to the upper layers of soil leading to problems like:
- Shallow rooting.
- Poor soil health- the soil may become anaerobic (anaerobic soils are pretty useless to grass and it will eventually die).
- Invasion of the lawn by pesky items- moisture-loving fungi and a range of other pests/pathogens thrive in such a habitat.
In other words, only lawns with an excessive thatch layer need attention.
Which brings me to the other key point..
Dethatching is NOT always the best solution for thatch!
Let’s discuss this a moment…
You see, dethatching can hit a lawn hard in several ways.
First, a dethatcher (a power rake can work as well) tends to tear and rip turf that’s still dormant and you can bet that often, the affected grass won’t recover after the procedure.
In addition, dethatching with power equipment could bring up crabgrass (plus all other nasty weed seeds) exposing your lawn to a possible infestation.
So, what safer options do you have?
1. Rake the thatch from your lawn
Tackle the thatch, yes, but use a thatch rake like this.
Simply grab a good dethatching rake and rake some of the formed thatch from your turf – done well, this is less stressful to the vulnerable grass and promotes quicker recovery.
Here’s the truth: raking is one of the best approaches for a thatch layer that is between ½” and 1 inch thick.
2. Aerate the lawn
When you aerate, (note that you should core aerate), you also get rid of the thatch- core aeration involves using a lawn aerator (features hollow tines) to remove plugs of soil or “cores” and thatch from the lawn.
This will boost air flow, reduce soil compaction, and aid root growth- of course, the right nutrients and water will also be penetrating all the way to the roots.
In most cases, core aeration is helpful for thatch layers 1-inch and under (recall that you only have to worry about thatch that’s at least ½-inch thick).
When to dethatch lawn….
Question: What if your thatch layer is more than 1″ thick?
Now, as you may have guessed, dethatching is justified for such extreme thatch buildup.
However, it must be said that dethatching should essentially be viewed as nothing else but a very last resort.
ALSO READ: When to power rake lawn
In reality, lawns only develop that much thatch because of ignoring some of the recommended care and maintenance procedures so very few lawns warrant dethatching.
For instance, proper fertilization and watering (combined with timely aeration) should keep the thatch at a healthy level.
With all that out of the way, here are the most prominent pros and cons of dethatching lawn you should be aware of.
My assumption is that you truthfully have a terrible thatch problem and it seems the only way out is dethatching your lawn.
Pro Tip: To measure the actual thickness of thatch, use a tool like a trowel to dig up a wedge-shaped chunk of soil and grass, about 3” thick. Proceed to measure the thickness of the brown-colored layer lying near the top of the soil.
Pros and cons of dethatching lawn – what you should know before dethatching (if necessary)
Pros of dethatching
- Lush grass- Water, fertilizer, sunlight, and pesticides reach the soil (and the lower grass blades) promoting revitalized growth (and deeper rooting).
- Prevent lawn diseases – No disease causing moisture is held against grass blades so common lawn diseases are less likely to strike your lawn.
- Healthier soil- Your soil is not going to become anaerobic.
- Easier maintenance- Thatch can create an uneven lawn which may cause uneven mowing/scalping and its removal makes mowing and other maintenance easier.
Cons of dethatching
The biggest drawback of the equipment-powered dethatching process is that a power rake or a tow-behind dethatcher is typically too aggressive and you’re almost sure it will hurt the grass.
Some patches of the lawn may, for example, remain bare in the aftermath particularly if the operation is poorly timed- timing is vital since you want your turf to have sufficient time to recover.
To be clear, dethatching should precede active grass growth to guarantee healthy recovery- warm-season grasses should be dethatched before the vibrant summer grow period while cool-season grasses should be dethatched in fall.
In a nutshell, it’s important to keep the pros and cons of dethatching lawn we have explained above before seeking the help of a professional lawn dethatcher or renting a dethatcher (if you’re a DIY enthusiast).
Don’t forget that dethatching is only practical when your lawn has a beyond-normal thatch problem – specifically when it’s over 1” thick.
One final reminder if you’ll be doing it: the right time to perform the procedure is determined by the variety of grass you have planted and climatic situations….
As mentioned, dethatch warm-season grasses before the summer and cool-season grasses in early fall.