Dethatching, if done incorrectly, can have some pretty devastating effects on your lawn. However, this doesn’t mean you should skip the dethatching process completely, as too much thatch has its own set of problems. So let’s answer the question, can dethatching hurt your lawn? And see what dethatching mistakes you’ll want to avoid at all costs.
Can Dethatching Hurt Your Lawn? (The Short Answer)
Failing to follow the correct procedure for detaching can result in extensive damage to a lawn and even kill it. Dethatchers are aggressive machines that must be set up correctly and used only during specific times of the lawn’s growth cycle. Dethatching under the wrong conditions can destroy the blades and roots of a lawn to such a point that it is unable to recover.
Dethatching Killed My Lawn (Here’s What You Likely Did Wrong)
Before you get into a position where you’ll be saying, dethatching killed my lawn, let’s look at some potential detaching mistakes you’ll want to avoid.
- Dethatching During Fall & Winter Dormancy
- Dethatching During Summer Dormancy
- Setting the Dethatcher Too Low
- Setting the Dethatcher Too High
- Using a Dethatcher When You Should be Using a Power Rake
Dethatching During Fall & Winter Dormancy
One of the first mistakes you might make is trying to dethatch your lawn during fall and winter while your lawn is dormant. Fall and winter is the point at which the soil temperature drops below about 50°F. When temperatures drop, the grass shifts its energy away from blade growth and down to the roots and crown.
This energy shift is the lawn’s process of protecting its vital structures to withstand the reduced temperature and lack of moisture. So, if you try to dethatch during this period, your lawn will refocus on blade recovery, which in turn reduces the protection of the vital structures. Dethatching when the grass is dormant is a big mistake you’ll want to avoid, as it removes the lawn’s defense mechanism and weakens the grass.
Dethatching During Summer Dormancy
Just as a lawn protects itself during the cold months, it also has the ability to protect itself from the high heat of summer. As soil temperatures reach around 85°F, your lawn will go dormant to protect itself. If you head out with your dethatcher during the hottest time of the year, you’ll disrupt this process and stress your lawn.
So, can dethatching hurt your lawn? Well, if you dethatch during the summer dormancy period, then the answer would be yes.
Setting the Dethatcher Too Low
Setting the dethatcher too low is a common mistake I have seen many people make. When you set the dethatcher too low, it digs into the root system and damages the lawns. Why is this a common mistake? Well, most people fail to do their pre-dethatching homework and are unsure what thatch is and how to measure it.
Thatch is the top layer of organic material that sits on top of the soil. It’s not just the brown grass clipping but includes all the organic material from the clippings down to the actual soil. So, if you have ½ inch of thatch and you set your dethatcher to cut an inch into the ground, then the dethatcher will not only remove the thatch but also clip the roots. Setting the dethatcher too low is definitely not a good idea and one easy way to kill a lawn.
Setting the Dethatcher Too High
If you set your dethatcher too high, then you won’t actually remove any thatch. Again this can happen when you mistake brown clippings for the thatch layer. If you only remove the top layer of clippings and not the rest of the thatch down to the soil, the thatch will accumulate to such a point that it begins to affect your lawn’s moisture absorption, air exchange, and nutrient uptake.
So even if you dethatch a couple of times a year, if the dethatcher is set too high, your thatch will increase, and your lawn will suffer.
Using a Dethatcher When You Should be Using a Power Rake
Two tools that I hear constantly being confused are a dethatcher and a power rake. So, if you are trying to dethatch your lawn with a power rake, you’ll have very little success. A power rake typically has small spring tines that rake out the clippings of a lawn, whereas a dethatcher has blades that tear down into the top compost level of the soil.
So, if you head out with what you think is a power rake to rake out grass clippings, but in fact, you are using a dethatcher, you’ll actually end up dethatching. This is fine unless you only have a thin layer of thatch. Why? Well, you’ll be dethatching into the roots of the lawn and killing your grass.
On the other hand, if you head out with what you think is a dethatcher but, in fact, it’s a power rake, you won’t actually remove any thatch. So, this is like having your dethatcher set too high. The thatch will continue to build up until it causes an issue.
For example, companies such as Greenworks sell machines called “dethatchers” that have metal tines resembling a garden rake… See how this can be confusing? Now if you look at a product such as a professional Ryan dethatcher and a Ryan power rake, you’ll see a clear and obvious difference.
Why Dethatching is Great for Your Grass (When Done Right)
If you dethatch the right way, then you won’t have to worry about if dethatching hurts your lawn. Instead, you’ll be able to focus on all the great benefits. Here are just a few of the benefits your lawn will experience when dethatching is done right.
- Improved Soil Drainage
- Improved Water Access
- Improved Nutrient Intake
- Improved Nutrient Availability
- Improved Soil Air Exchange
- Improved Root Respiration
- Improved Grass Blade Reparation
- Improved Soil Temperature Regulation
- Increased Soil Aerobic Microbes
- Decreased Soil Anaerobic Microbes
- Reduced Lawn Disease
- Reduced Lawn Pests