Summer jobs: How to scarify & aerate a lawn

Hot weather with regular watering is the ideal chance to give your lawn a boost by scarifying, the aerating the turf. This will improve growth, soil drainage and help it grow into autumn and beyond. The warm summer weather means it’s the perfect time to give your lawn a helping hand.

What are scarification and aeration and why are they important?

As mentioned above, your lawn needs a helping hand to avoid compacting down, and to help water reach the deeper root networks of your lawn. This can be done with aeration, which involves gently puncturing the surface of the soil to improve drainage and create spaces for microscopic life that will help break down nutrients.

Scarification involves gently raking the lawn, either with a special tool or using an electric or petrol driven machine, to remove dead organic matter, such as moss or ‘thatch’ that builds up around the lawn. The treatment should be performed throughout the year, in particular in spring and autumn, however more frequent scarifying is recommended, especially for finer, more demanding luxury grass types.

When considering both aerating and scarifying, it’s better to scarify first, then aerate- but leave a few days in between the two exercises to allow your lawn to recover before you put it through all that work again.

How do you scarify your lawn?

Scarification itself can be quite a straightforward process (though labour intensive without machines). However, as with much in the world of lawn-keeping, getting the conditions right beforehand is important.

You don’t want to scarify a wet lawn, yet do ensure it’s been recently fed. Water your lawn beforehand then allow it to dry. Add moss killer to loosen up any build up before scarifying.

This can then be lightly raked away and disposed of. Gently removing this kind of build-up, known as thatch, allows better absorption for fertilisers, increased the amount of sunlight reaching your lawn and is a great way to improve the overall health of your turf and the quality of your lawn.

If allowed to go unchecked, thatch build-up often results in a slightly springy, spongy surface, poor water and nutrient absorption, off-colour grass and provides a habitat to pests such chafer grubs which can develop beneath. For these reasons, you should try and scarify a lawn semi-regularly, in spring and autumn especially.

How do you aerate turf?

Unlike scarifying, aeration doesn’t involve removing build-up, rather it’s about helping the soil beneath grass breath, by puncturing the ground with special spiked tools, creating tiny holes in the surface.

This provides space for water & fertiliser to drain into the root systems as well as creating enclaves for microorganisms whose ability to break down nutrients will provide a long-term boost to the lawn.

It also means any areas of compacted earth- such as in high-traffic areas, is loosened up and allowed to sit less densely under your grass, making a more even surface in terms of nutrient absorption- and therefore leading to less patchy or unhealthy grass.

As with scarification, if left under-aerated or compacted lawn can lead to poor water absorption, a build-up of thatch and unhealthy, off-colour grass.

Lots of tools exist to make aeration easier- from machines to rollers to spiked shoes, to the simple garden fork. If you choose to improvise, puncture the lawn down between 2 and 6 inches, as much as you can but keeping it even.

As with scarifying, don’t do if your lawn is wet but do feed it beforehand- and allow the turf to dry.

What’s next?

After you have aerated and scarified your lawn, spread grass seed evenly on the lawn to take advantage of the newly-available space you’ve just created to promote a thick, luscious lawn. You could also consider top-dressing your lawn to improve drainage.