Should You Scarify or Aerate First?

If your lawn is spongy, mossy or full of thatch, you have probably heard that scarifying and aerating can help. But which should you do first, and do you really need both on a typical UK family lawn?

Here is a straightforward order that works well for many gardens, plus some tips to avoid overdoing it.

Video: scarify or aerate first?

This video looks at the pros and cons of different orders and explains how each treatment works on the lawn.

What scarifying does

Scarifying uses blades or tines to pull out dead grass, moss and creeping stems from the surface of the lawn.

• It helps new grass grow into the spaces that are freed up.
• It can look brutal immediately afterwards, but is often worth it in the long run.
• It is best done in spring or early autumn when the lawn can recover.

What aeration does

Aeration punches holes into the soil to relieve compaction and improve air and water movement around the roots.

• On clay or heavily used lawns, it can really help drainage and root health.
• It is usually done with hollow tines (which remove small plugs) or solid spikes.
• It is often combined with top-dressing and overseeding.

Why scarify before aerating?

In most cases it makes sense to scarify first and aerate afterwards.

• Scarifying removes surface material that would otherwise fall into the aeration holes.
• Aeration after scarifying helps new seed and top-dressing work deeper into the soil.

When to be gentler

Very weak lawns can be damaged by heavy scarifying and aeration.

• If the lawn is mostly moss and soil, consider a lighter rake and careful overseeding first.
• Build strength with feeding and mowing before attempting aggressive renovation.

Frequently asked questions

How often should I scarify and aerate?

Many lawns only need scarifying every couple of years, with light raking in between. Aeration can be done as needed, particularly on compacted or wet areas. Some lawns rarely need deep aeration at all.