Garden guide

Top Dressing a Lawn: What It Is and How Much You Need

The short version

Top dressing is a thin layer of sandy soil mix brushed over the lawn to level hollows, improve drainage and feed the grass. Done after scarifying or aerating in spring or autumn, it's the quiet professional trick behind stripey, billiard-table lawns.

What's in the mix

The classic mix is 70% sharp sand to 30% screened topsoil (often with a little compost) — free-draining so it never smothers the grass. Heavy clay lawns benefit from a sandier mix; thin sandy soils want more loam. Buy it ready-mixed as lawn top dressing, or blend your own.

When and how to apply

September or April, on a dry day, ideally right after aerating or scarifying. Shovel small piles around the lawn, spread with the back of a rake, then brush it in with a stiff broom until the grass tips poke through. Never bury the blades — 2–3mm is plenty, and 5mm is the absolute ceiling.

How much do you need?

At 2–3mm deep you need roughly 2–3 litres per m². A 50m² lawn takes 100–150 litres — one bulk bag with plenty spare. Levelling deeper hollows: fill them in stages a centimetre at a time, letting the grass grow through between applications.

Working out the cost

Our topsoil calculator converts your lawn area and dressing depth into litres and prices bulk bags against handy bags — the same maths works for any sand-soil dressing mix.

Open the topsoil calculator

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