What is Dethatching?

What is Dethatching?

Dethatching is one of the most overlooked tasks in lawn care and lawn maintenance. The thatch layer is made up of brown decaying plant matter just above the soil which builds up and prevents nutrients and moisture from reaching turf roots.

This layer is also a friendly environment for fungus to grow. Even though thatch is regarded as a detriment to a healthy lawn it also has positive qualities in that thatch can prevent weeds from geminating, hold in moisture and protect grass from frost damage. There is a general rule that more than ½ inch of thatch is not beneficial so keeping an eye on thatch thickness is very important.

Dethatching – A Timely Task

The best time to de-thatch a lawn is in late spring and early fall when grass growth is most active as it can bounce back from stress more quickly. As mentioned above a thin layer of thatch can protect against frost damage so if you see frost, it is better to refrain from de-thatching your lawn.

If you forget to de-thatch your lawn in late spring do not do so during mid summer because you are removing the protective layer that is often needed for soil water retention during times when mild drought conditions are present.

You also want to avoid de-thatching when weeds are germinating, this can cause an explosion of weeds you didn’t even know existed. De-thatching is a timely task and is at the root of most issues for lawn care and maintenance.

To determine the depth of thatch you can cut a small square of sod out of your lawn and measure the depth of the thatch, but most people just pull aside their grass and estimate the thatch thickness. Some lawn care experts can determine how much thatch is underfoot by the feel of the bounce of their step on a lawn.

How to De-thatch

The best way to de-thatch a small lawn is with a thatching rake which has thick blades designed to pull thatch out of turf without pulling up the grass itself. For larger lawns rent or buy a vertical mower (a.k.a. dethatcher) which has rotating blades that scrape, cut and remove thatch from turf.

DO NOT de-thatch a lawn and leave it bare, follow up with lawn aeration, fertilizing and watering to support the lawn during its growth cycle.

I see thatch as the yin and yang of lawn care and lawn maintenance. If you have too little thatch at the wrong time of year, weeds will germinate and lawns can either burn or freeze depending on the conditions. It is smart to write down de-thatching times and take this task very seriously, if you do so you are going to be rewarded with balance in the form of a greatly improved turf.

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