How to Rake & Scarify

Mowing Before Scarifying

The first step is to mow the lawn as close as possible without scalping. Keeping it short will make the process more effective and should be maintained until seeding is complete.

Choosing the Right Tool

Wearing leather gloves with talc will help prevent blisters if using a hand-held rake. Moderate pressure is required, and multiple passes will be necessary to lift out moss and thatch. A lawn scarifier with wheels is a far better option. It reduces the physical strain, allows gentler action, and is just as effective. An electric rake also works well but repeated runs up and down the lawn will give the best results. A petrol scarifier provides more power, but it’s essential not to go too deep. The best approach is to start shallow and gradually work deeper with each pass.

Setting Up Your Machine

Setting the machine correctly is critical. Adjust the height on a hard surface and turn the machine off so the blades or wires touch the ground. A short test run on the lawn will help fine-tune the height so debris is removed without tearing up large chunks. The aim is always to tease the material rather than rip through it.

Clearing Debris

Once the debris has been loosened, the collection is necessary. A landscaper’s or hay rake, about two to three feet wide, is ideal for gathering moss and thatch. A lawn mower is also a useful tool for this stage. Running the mower over the lawn helps compress the debris, making it easier to collect, and gives the lawn another trim. If using a scarifier, leaving the collection box off may help clear the lawn more efficiently. Regular collection throughout the process will ensure the scarifier continues working effectively if excessive moss or thatch occurs.

Direction and Depth of Scarifying

Changing direction for each successive pass will improve results. A direct right-angle change should be avoided, which can cause excessive damage. Each run will remove more debris, progressively thinning the moss and thatch. As the lawn clears, the machine can be lowered slightly for a deeper cut. If using a scarifier with blades, allowing the machine to penetrate the soil by up to a quarter inch can be beneficial, especially if overseeding afterwards. However, keeping electric lawn rakers or wire tines off the soil is best to avoid excessive damage and prevent breakage.

How Far to Go

Deciding how far to go depends on the condition of the lawn. If moss or thatch levels are low, or the process is being done in spring, two passes should be enough, one in a straight line and another diagonally. Keeping the machine at a slightly higher setting will minimise damage and ensure a quick recovery with rain and fertiliser. If the lawn has a severe thatch problem and conditions are suitable, four or five progressively deeper passes may be necessary. The result may look extreme, even worrying, but with the proper care, the lawn will return healthier and stronger.

Addressing Uneven Lawns

If bumps in the lawn cause excessive damage during raking or scarifying, they may need to be corrected separately. Damage in these areas is almost inevitable but shouldn’t be a concern. The lawn will bounce back in a few weeks with proper recovery steps. If the lawn has shallow dips, top dressing after scarifying with three to four kilos per square metre of material can help even things out. Applying the seed before top dressing is generally the better approach if overseeding.

Handling Severe Thatch Issues

Sometimes, thatch is so bad that, as explained earlier, the lawn has rooted into it. In this case, either great lumps of lawn will pull away, or you will end up with just thatch and no grass. In this case, you need to consider whether neglect is the cause or if soil compaction and disease are the cause. If it is the latter, consider a new lawn. If it is the former, keep going with the scarifier until you get down to the soil. The likelihood will be that, in a heavy thatch situation, you will remove most living grass; therefore, you will have to re-seed the lawn.

Additional Lawn Care

This is also an ideal time to aerate the lawn. Hollow tining or spiking can improve soil structure and aid recovery. If tackling moss rather than thatch, it’s not always necessary to kill the moss before scarifying. For more details, check the Moss Control guide.

By following these steps, the lawn will be set up for better growth and healthier grass, making all the effort worthwhile.