How Do I Fix Compacted Soil in My Lawn?
Compacted soil is the hidden cause of weak, yellow, mossy lawns. Learn how to diagnose compaction and fix it with aeration, top-dressing, and the right tools.
Diagnose the Problem
Compaction is the silent lawn killer. When soil particles are pressed together, water, air, and roots can't move through it. Grass starves, moss thrives, and weeds move in. It's the root cause of many lawn problems.
High foot traffic
Children playing, regular walking routes, and pets all compress soil over time.
Heavy rainfall on clay
Clay soils compact naturally when wet and then dry hard.
Mowing with heavy mowers
Repeated passes with heavy ride-on mowers compact the soil beneath the wheels.
New-build soil
Construction traffic compresses subsoil before turf is laid, leaving a hard layer beneath.
The Solution
The fix is aeration — creating channels for air, water, and roots. Here's how to do it properly:
Test for compaction
Push a garden fork into the lawn. If it barely goes in, the soil is compacted. You'll also see water pooling on the surface after rain.
Choose your tool
For light compaction, a garden fork works. For serious compaction, use a hollow-tine aerator which removes cores of soil, giving the best relief.
Aerate when soil is moist
Aerate in spring or autumn when the soil is damp but not waterlogged. Dry soil is too hard; waterlogged soil smears and seals the holes.
Go deep and spaced
Push the fork or tines 7–10cm deep, every 10–15cm across the lawn. Hollow-tine in lines for even coverage.
Top-dress and feed
After aerating, brush a 70/30 top dressing into the holes to keep them open. Then feed so nutrients reach the newly opened root zone.
Use the Soil & Topsoil Calculator
Calculate how much 70/30 top dressing you need to fill aeration holes and level your lawn.
Recommended Products
Shop 70/30 top dressing, sandy loam, and aeration tools to relieve compaction and improve your lawn.
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