Dethatching your Lawn

Dethatching Lawns

Love your Lawn? Dethatching is an essential part of lawn maintenance. Today we will be showing how to fix a very common issue found in most New Zealand lawns.

In the long run dethatching will save you serious money. You won’t need to water or fertilise you lawn nearly as often.

Now you know the importance, let’s show you what it’s all about.

What is Dethatching?

Before we explain how to dethatch your lawn, we’ll quickly explain what thatch is.

Thatch is the organic layer of shoots and roots that accumulate near the surface of the soil.

It’s basically an unseen net which keeps out the valuable water you’ve spent time spraying on your lawn.

Photo credit: alaskapremierservices.com/lawn-dethatching/

Excessive thatch can also prevent oxygen reaching the soil. That leads a range of issues down the line.

You can find these issues and solutions in our aeration blog.

When should we Dethatch?

This will depend on what grass makes up your lawn.

For Ryegrass and Fescue lawns, you will want to dethatch in late summer through to early autumn. This applies for any cool season grass.

If you have a Kikuyu lawn you should dethatch your lawn in mid to late summer. This generally applies to all warm season grasses.

You should dethatch your lawn when it gets to around ½ inch deep. The best way to check the level of thatch is simply checking how much bounce your lawn has.

A dense bouncy lawn will indicate a build-up of thatch.

How Do We Dethatch?

There are several options you have when dethatching.

All methods first require you to mow your lawn prior to commencing.

The first way is by using a convex or thatching rake. You can find these at your local hardware store.

Raking the grass will loosen and lift up thatch. You can then use a leaf rake to easily rake the thatch into piles and then discard.

This option is perfect for small lawns.

The next method is to use a dethatcher (also known as a vertical mower or a power rake).

This will require a trip to the hire shop, but well worth the time if you have a large lawn.

Photo credit: http://www.kerttechnika.hu/index.php?page=cikkek&page2=magazin2&rovatid=14

A dethatcher has revolving blades that cut through and bring thatch to the surface.

To use the machine, run it across the lawn in a line as you would a lawn mower. Then run the dethatcher across the lawn again at an angle perpendicular to the first pass.

Rake up the lifted thatch and dispose.

About.com has a great video which explains how to dethatch a lawn:

Please note when Barry George talks about fall he is talking about autumn.

If you would like to see how a full lawn repair is done:

This Old House includes dethatching in this video: 

Dethatching after Care

There are several tasks that can be done after dethatching.

It’s recommended that you aerate your lawn. You can find more information in our Aeration blog.

Once your lawn has been dethatched and possibly aerated, you have a great opportunity to get nutrients into your soil.

Added compost or fertiliser at this stage will benefit your lawn greatly. You will need to water you lawn after these steps.

You then look into topdressing you lawn with some quality lawn soil or as previously mentioned compost. You can find a comprehensive guide to topdressing here.

There many steps to maintaining a lawn. For those that persist a healthy lush lawn can be easy kept.