Lawn thatch is a natural process in turf and some grass types create more than others. Organically maintained turf rarely have thatch problems. When or how to dethatch lawns is usually answered by what methods your grass is treated throughout the growing season. Thatching a lawn is easy but you will need to rent a thatching machine.
Brief anatomy of a grass plant
Grass plants spreads by stolons (tillers) and rhizomes. As the rhizomes and tillers continue to grow they create additional grass plants. Those spreading plants also produce their own roots and grass shoots thus providing a dense thick green lawn.
This spreading and reproducing creates a tangled mat out of the living and dead plant material.
That is what creates lawn thatch
Without our interference of over watering, chemical fertilizers and pesticides, lawn thatch breaks down naturally as just another simple process by nature. A healthy diverse population of fungi has no problem keeping thatch in check.
Synthetic fertilizers and fungicides kill the fungal properties in the soil so there is no natural defense to the build-up of lawn thatch.
A bit of thatching is good as it cools the soil surface in the summer.
Too much thatch and:
- It hampers air
- Water getting to the soil,
- Increases insect and disease issues
- Prevents the lawns natural spreading process
- Stolons can’t make soil contact if the thatch is too thick
- Amendments you add have a tough time reaching the soil
Over watering and applying too much nitrogen are main contributing factors in the build up of thatch. 1 – 1/2 inches of water a week and 3 pounds of nitrogen a year should keep the thatching machine, also known as a power rake, at the rental store.
Organic lawns do not have thatching issues.
Grass clippings do not cause lawn thatch!
There is a misconception that not bagging grass clippings creates thatch. Call it an old wives tale or an urban myth, the bottom line is it just simply is not true.
Freshly cut grass blades consist of approximately 90% water and begin to break down quickly, then proceed to feed the bacteria in your soil.
- Less work emptying the mower bag
- Provides 1 lb. of nitrogen per year
- Feeds the bacteria
- Please recycle the clippings back into the lawn
I’ll see landscaping companies thatching lawns as their regular spring ritual. They’ll say “Well it lets the grass breath or it helps the lawn look nice and clean after winter.”
The answer to that is, if you didn’t apply so much unnecessary fertilizer all season you wouldn’t have the thatch problem in the first place.
Creating a problem means the situation has to be resolved, which in turn are billable hours. Then again, most of them don’t even know they’re causing the thatching problem.
If you hire landscapers to remove thatch, demand they let nature do it’s job and save you money. There are plenty of other services they can sell you. Don’t buy into “organics don’t work routine” it does work you just have to know a little about how a lawn grows.
When to thatch a lawn
When transitioning a lawn from years of synthetic fertilizer use to organic, the build up of lawn thatch will probably be excessive. In this case
using a mechanical thatching machine is appropriate.
Also, when renovating or overseeding your lawn for the first time it will also be necessary.
Why not use a thatching machine?
Let’s take a look at how it works. It’s got these tines turning at rapid speed slicing and shredding the lawn. It tears up a great deal of healthy grass leaving bare spots and just simply stressing out the lawn, creating an invite for more problems like weeds and insects.
If you’re not sure if you need to use a thatching machine apply a fungal dominated compost tea first.
A few applications of tea should remedy problem lawn thatch as long as it isn’t too thick.
If the layer is 1 – 1/2 inch thick you can use a vertical slicing machine. Once is okay. After removing the thatch, if your levels reach over 1/2 inch again, then there is something you’re not doing
correctly and you need to get those fungal properties into the soil.
Another effective way to eliminate lawn thatch if it isn’t to thick is to aerate your lawn. The plugs left on top of the lawn thatch help decompose the excess layer.
Topdressing your lawn with a light coat of healthy compost is also a nice natural step in eliminating excessive lawn thatch.
How to Use a Thatcher
People will thatch in the spring in cool zones and that’s the worst time to do it. It leaves bare spots giving weeds room to germinate. Don’t use a power rake in the heat of summer as it could damage your lawn. Early autumn when it’s cooler and the threat of weeds subside, is when you should remove thatch in cool zones.
If your place in the world is in what is considered a warm zone, you should remove lawn thatch in early spring.
If your thatch is thick, removing it before you overseed is crucial. It will impair the important seed to soil contact.
This machine can be rented out for half a day for around $25 – $30. Depending on the size of your lawn it shouldn’t take to long to use it. Do it when the lawn is dry.
Make sure the machine is set correctly to slice into the ground no more than 1/8 to 1/4 inch. Try not to go to deep leaving bare soil patches.
It’s just like mowing your lawn, back and forth overlapping your wheels. These aren’t self propelled machines but its momentum will move you rather easily.
Do a good job if the thatch was excessively thick you can always go over it again perpendicular to your first direction.
Use your own judgment
It’s the last time you’ll be using this machine so do it right
If you have a blower, cleanup is easier and more efficient. Blow it into a big pile and realize that it’s the last time you’ll see that pile on your driveway because you no longer use synthetic fertilizers.