How to deal with lawn thatch


Something lawn owners will most likely face at one point in their garden and lawn maintenance journey is thatch. The best lawn turf providers and experts, Joondalup Turf Farm, dig into thatch, what causes it, when you should dethatch and how you dethatch your lawn. 

What is lawn thatch?

Thatch is made up of tightly intermingled layers of stems, leaves and grass roots that accumulate between vegetation and the soil. 

Having too much thatch increases your turf’s susceptibility to lawn diseases, reduces its tolerance to drought, cold, and heat stress, as well as hindering the movement of air, water, fertilisers, and nutrients into the soil.


What causes thatch build-up?

Thatch commonly occurs in lawns that have ‘dead soils’ and tends to be symptom of the absence of beneficial microbial activity. 

It accumulates in a lawn if the production of dead material, also known as organic matter, exceeds the ability of the microorganisms in the soil to break down the organic matter. 

Some of the specific causes of thatch build-up includes over watering of your lawn, shallow watering, fertilising with salt based nitrogen, mowing your lawn infrequently, as well as compacted soil that has not been aerated. 


When should you dethatch your lawn?

We recommend dethatching warm-season grass such as kikuyu, couch grass, zoysia, and buffalo lawn in late October to early December, after giving the grass time to recover from winter. 

It is advised that you try not to dethatch too late in the growing season, otherwise your lawn may not be able to recover throughout the winter. 

You should keep in mind that certain kinds of dethatching methods are not recommended for cool-season grass. 

How do you dethatch your lawn?

There are a number of tools you can use to dethatch your lawn including a special dethatching rake, a lawnmower, a power rake, and a sacrifier. Find out more information on how to use these different tools below.


A dethatching rake is one of the manual ways to dethatch your lawn and is likely the most inexpensive option but is also the most labour intensive. 

This method is a slower process and is not particularly practical if you have a large area that needs dethatching. It is also worth remembering that you will have to do this twice a year at the least.


You can also remove thatch by way of scalping which means you would mow your lawn as close to the soil or ‘scalp’ as possible.


A power rake is another alternative you could use and is a specialised machine created for this very purpose.


Scarifier’s are also commonly referred to as dethatchers and are a much more aggressive approach than a power rake. The great thing about scarifiers is that they not only remove surface thatch but digs right through the soil.


We advise renting this machine twice a year as it can be quite expensive to purchase. 

To use power rakes for dethatching, you have to make sure that your soil is moist but not soggy. If the ground is too moist, the healthy grass might get pulled out along with the thatch. 

If you aren’t familiar with how deep to set the tines, pass over a few spots using the power rake and adjust accordingly. Position the tines so they can reach deep enough to rake off the thatch but not too deep as to dig out the soil. 

You may need to do two passes over the lawn with the power rake to ensure that all unwanted thatch is removed.


Your go-to for grass maintenance tips!

Joondalup Turf Farm not only provides you, our customers, with a range of high quality grass varieties, but we’re here to help with any after care queries you might have after installation. 

To receive more advice on lawn care or lawn thatch, or call our team on (08) 9404 7821. Phone lines are open every day from 8am to 7pm. You can also pay us a visit in person and speak to one of our lawn experts at 187A Lakelands Drive, Gnangara WA 6077.

For more lawn tips and information be sure to keep an eye on our website!