Your lawn is obviously not static. It’s in a constant state of change. Even if to the human eye there doesn’t appear to be a lot going on, there is.
If you’ve noticed some parts of your lawn looking worse for wear (maybe some browning of the tips) and the grass appears to be struggling, you might get told to dethatch your lawn. But what exactly does this mean and what are the pros and cons of dethatching your lawn?
What Exactly is Lawn Dethatching?
Before we get into the pros and cons of dethatching your lawn, I should really explain what it actually is, as I’m assuming you’ve probably never done it before.
Lawn thatch is a layer of dead grass roots, rhizomes and stems that builds up over time and creates a layer on top of the soil. Thatch isn’t necessarily always bad. Depending on the type of grass that you have, it can provide your lawn with extra protection from foot traffic, temperature fluctuations and water loss.
But once the thatch builds up past a certain point, normally more than ½”, it can start to have a detrimental impact on your lawn’s health as it can stop water and air from getting to the roots. At this point your need to dethatch it. Lawn dethatching is the process of removing this layer of thatch.
Pros of Dethatching Your Lawn
There are numerous benefits to dethatching a lawn. The following are what I consider to be the main ones.
Allows Air and Water to Get to Roots
Both of these resources are very important to a healthy lawn, but when the thatch layer is too thick, the water is soaked up (the thatch acts like a sponge) and the air just can’t get through. When this happens, it’s rather like someone putting their hand around your throat. You can’t drink and you can’t breathe. And just like you would change color, your grass does too, often going either yellow or brown.
With your lawn dethatched, the grass has access to both of these things again which will go a long way to restoring it to a lush green color.
Grass Gets the Nutrients It Needs
All plants need nutrients to thrive and grass is no different. There are three primary nutrients that it needs, which are nitrogen, phosphorus and potassium. But even if you apply the perfectly formulated fertilizer to your lawn, if there is too much thatch, it won’t be able to absorb it.
One of the other big pros of dethatching your lawn is that nutrient uptake will be boosted significantly and that will stimulate growth and improve the condition of your lawn without doubt, and very quickly too.
Your Lawn Will Actually Drain
If you have heavy rainfall in your area and days later the water is still sitting on top of your lawn, it could be a sign that the ground beneath it is extremely compacted and aeration is necessary. But it could also be a sign that there’s too much thatch. You see a heavy layer of thatch is rather like when you get a load of crap accumulate in the bottom of your sink. It can’t drain, or it drains extremelllllly slowly at best.
And having stagnant water just sitting there obviously isn’t good for your lawn. It can cause a whole host of problems with lawn pests and disease.
Dethatching your lawn helps to remove this natural plug and your lawn will drain much better afterward so you can avoid all of these problems.
Reduces Risk of Lawn Disease and Pests
I have just touched on this, but I’ll go into a little more depth here. Maintaining a healthy lawn is hard enough, without having to deal with the many lawn diseases and pests that can attack it. Too much thatch will increase the risk of these and at the same time, with your lawn in a weakened state due to its reduced access to water, air and vital nutrients, it won’t be as capable of fighting them off.
In particular, Red Thread, Microdochium Patch, and Leaf Spot are diseases that are common in lawns that have a heavy layer of thatch. And chinch bugs are one type of lawn pest that targets lawns with lots of thatch.
Cons of Dethatching Your Lawn
It’s important to look at both the pros and the cons of dethatching your lawn before you decide whether to do it or not. So here are some cons for you to consider.
A Little Thatch Can Be Beneficial
Many people have this misconception that all thatch is bad. Whether it’s ¼” or 1 ½” it all has to go. But that’s not true. A little bit of thatch can actually be very beneficial to your lawn. It provides insulation in colder weather, offers protection again strong direct sunlight and reduces the amount of water a lawn will need to sustain itself. Thatch also acts as a natural buffer to protect the lawn from foot traffic, and it can also turn into a natural source of vital nutrients when broken down by earthworms.
Dethatching your lawn will remove most if not all of the thatch build-up, taking away these benefits.
It Can Be Damaging If Done At the Wrong Time
The same way that cutting your lawn too short can shock your lawn and make it more susceptible to numerous lawn diseases, dethatching causes significant stress to lawn grass, and if done at the wrong time of the season it can have serious consequences.
Dethatching should be done at the time of the season when the grass is growing, as if it is done when the grass has gone dormant, it may not be able to recover. The same goes if it’s starved of a certain resource, such as during a drought. Dethatching during these periods can kill off your lawn or at the very least seriously harm it, so it’s part of your lawn maintenance that needs to be carefully planned.
A Quick Summary
Here’s a quick rundown of all of the benefits of dethatching a lawn:
- Air and water will be able to reach grassroots
- Uptake of vital nutrients will be improved
- Your lawn will be able to drain and won’t retain water
- The risk of your lawn falling victim to lawn diseases and pests is reduced
And here are some cons of dethatching that you should be aware of:
- A minimal amount of lawn thatch (1/2” or less) actually provides several benefits – protection from extreme temperatures, water retention, resistance to foot traffic – and these benefits will be lost.
- Dethatching can cause considerable stress to the grass and it will be temporarily weakened, which is why it’s important to only dethatch during the growth period of the season (this will vary according to whether you have a cold season or warm season grass).
Dethatching can be a valuable tool in every lawn owner’s arsenal when used correctly. I hope this guide has given you a better idea of what to expect from the process.
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