Our other sites:

How to scarify a lawn with a rake

Shop for Rakes

If thatch builds up too much on lawns it can damage it, thatch rakes can be used to dethatch grass Scarifying a lawn is a way of removing the build-up of thatch and moss which can accumulate at the roots of grass and scratch the soil’s surface, aerating it slightly. Scarifying is often called thatching or dethatching because it will remove thatch.

Thatch

Thatch builds up on grass and can cause problems. Thatch rakes are designed to make removing thatch easier

Thatch is a build-up of dead and dying grass roots, shoots, runners, and other living and dead plant materials.

Thatch rakes are designed to remove thatch from lawns Thatch building up underneath healthy grass may be obvious when it starts to become excessive. When lawns look brown and unhealthy they might have excessive thatch. If grass feels spongy as you walk on it, this could be thatch building up.
Wonkee Donkee says "Sometimes grass can look brown due to disease. Raking diseased grass can spread it across the lawn."
when thatch builds up in lawns it can cause problems, you can use a rake to remove thatch To measure the amount of thatch on a lawn, the best way is to cut out a sample section. You can remove a core of soil with a shovel or trowel and actually measure the thatch. Thatch build-up is considered healthy when it is about 13mm (0.5″), once it gets thicker than this, it can start causing problems.

Moss

Moss can build up on lawns, pathways and in planting beds. You can remove moss with a rake Mosses are small plants which usually grow in clumps or mats. Moss will occur naturally on moist and shaded gardens, pathways, trees and other surfaces. Moss can help soil to retain moisture, but it can cause problems if it becomes excessive, and can kill grass.
Thatch rakes can pull up moss Excessive build-up of moss on grass will usually be a symptom of a lawn which has weak turf, is too moist, or is very shaded. If left to grow moss can starve the grass. Other factors which can affect a lawn’s conditions, and encourage moss growth, include drought, soil which is heavily compacted or clay, low levels of nutrients in the soil, and the grass being mowed too short.

When is the best time to scarify a lawn?

If you remove moss or thatch with scarifying you should wait for good growing conditions before you rake the lawn. It’s best to scarify a lawn at a time of active growth – you need the grass to be growing to recover. If the grass is growing well before you scarify, it should continue to grow aftewards. The best growing conditions for grass are when there’s sun, rain, and warmth. The grass will normally take two to four weeks to recover in good conditions.

Before you begin

Raking live moss can spread the spores. Choosing the right rake will make moss removal easier

Kill moss

If you have a problem with moss you will probably want to apply a moss killer and wait for the moss to die before you scarify. This is because raking live moss can spread the spores and make the problem come back worse. This usually takes one to two weeks.

Before you scarify a lawn you should mow it. Us a thatch rake to scarify a lawn

Prepare lawn

It’s easier to remove dry moss and thatch. However, the soil should be damp to prevent damaging it. If the soil is very dry you should water it a couple of days before you plan to scarify.

Mow the lawn before you scarify – this will make it easier to see the thatch. Set your mower a little shorter than usual.

Scarifying

If you're dethatching or scarifying a lawn you'll probably want to work in small areas at a time

Step 1 – Choose an area to start

It is best to scarify small areas of a lawn at a time. This will make it easier to see which areas you have done and which need doing. You don’t need to physically mark out the area, but have a plan of how you will cover the whole lawn a bit at a time.

Hold the rake comfortably with both hands for dethatching lawns

Step 2 – Hold rake comfortably

You might have to rake an area of lawn a number of times to remove all the unwanted materials, so you’ll want to feel comfortable as you work. Stand with one foot in front of the other. Hold the rake with both hands, one nearer the head than the other.

Pull the rake towards you to scarify the lawn and remove thatch and moss

Step 3 – Rake lawn

Dig the rake’s tines lightly into the thatch or moss and pull towards you, lifting at the end of each stroke to pull the thatch and moss to the surface of the grass. You don’t want to be too rough or you will damage the healthy grass and soil. Work in one direction, going over the same area a number of times.

Remove thatch from the tines or teeth of the rake as you work to dethatch a lawn As you rake you should notice the thatch or moss coming out from around the living grass. Moss and thatch will probably get stuck in the tines of the rake; remove this debris regularly to ensure the rake stays effective.
Rake in one direction first then rake at an angle to dethatch a lawn

Step 4 – Change direction

Once you have raked one area in one direction a few times, change the direction. You should rake over the same area, moving the rake at an angle of between 45 degrees and 90 degrees to the direction you raked the first time. This should bring up more debris.

Rake over the area more than once to remove thatch or moss

Step 5 – Repeat

Repeat this process on the next area of lawn. Continue to rake in small areas at a time until you have covered the whole lawn. The moss, thatch, and any other debris can be gathered and disposed of.

after scarifying a lawn with a rake or dethatcher you should water and fertilise it

Step 6 – Aftercare

Once a lawn has been scarified you should water and fertilise it. Make sure you don’t over fertilise the lawn – this is a common cause of excessive thatch build up. The grass can then be left to regrow.

Wonkee Donkee says "As long as you haven’t used any herbicides or pesticides in the last month, you can use the moss and thatch you remove from your garden to feed your soil by composting it."