Scarifying your Lawn (Video) | BBC Gardeners World Magazine

What is scarifying?

If your lawn has developed lots of bare patches or moss, you probably need to scarify it. Scarifying a lawn is simply the process of removing dead thatch (the brown material found beneath the green grass blades). A small amount of thatch is a good thing in lawns, but in large quantities it can inhibit growth of new grass, prevent water and nutrients from reaching the roots, and encourage moss to form.

To scarify a lawn you will need a rake or scarifying machine. You, in effect, scratch the grass to remove the thatch – it can look unsightly initially but if you trust the process you'll have a lush, green lawn in no time.

Aim to keep the amount of thatch in a lawn less than 1cm deep. Any more than that will result in a patchy lawn with lots of moss, but less than 1cm could damage the lawn.

When should you scarify a lawn?

Scarify your lawn in spring or early autumn (well ahead of the first frosts), ideally once a year, to keep the lawn in good shape. On new lawns, wait at least a year before scarifying, otherwise you can damage the turf.

How to scarify a lawn

Using a spring-tined rake, gently rake the thatch out of the lawn – you'll soon notice brown, grassy material and moss piling up. Be careful not to be too rough, as you could cause damage, and make sure you leave some thatch – a small amount helps to protect the lawn. Work in different directions to ensure the thatch comes out evenly.

What to do after scarifying a lawn

After scarifying, pick up the spent thatch and add it to the compost heap. Then, it's a good idea to aerate the lawn, which reduces compaction and creates a healthier root system. Simply use a garden fork and push it into the ground at regular intervals, moving it back and forth.

After scarifying and aerating your lawn, it will look worse than it did when you started. You may want to apply a fertiliser to boost lawn growth or leave it to recover on its own, but it will definitely be healthier for a good annual scarifying.

Inspired by Alan's tutorial? Our experts have tested a range of manual and powered aerators and scarifiers - check out the best scarifiers and best aerators reviews.