How to mow your lawn properly

Mowing well — right height, right time of year, sharp blade, cut direction varied — is the rhythm a healthy lawn is built around. Most of the work happens in this routine itself; the details below are about getting the routine right.

Why this matters

Grass is a plant that wants to grow. When you cut it, you remove the part it photosynthesises with — and it has to spend energy regrowing leaves before it can put energy into roots, into colour, into thickening up. The "one-third rule" exists because cutting more than a third of the leaf in one go shocks the plant: it stops root growth for days, exposes the soil to weed seeds, and turns yellow.

Frequent, shallow cuts beat occasional aggressive ones every time. A lawn cut weekly at 35 mm will outperform the same lawn cut fortnightly at 25 mm. The difference is shocking once you see it.

When to do it

The growing season — March through October in most of the UK. Outside that, the grass is barely growing and a cut does more harm than good.

• Spring (Mar–May): ramp up gradually. First cut at the highest setting once new spring growth reaches around 5 cm tall, then bring the height down step by step over the next few cuts to reach normal seasonal height.
• Summer (Jun–Aug): weekly minimum, twice a week if you've fed and watered. Raise the cut to 30–40 mm in heat — taller grass shades the soil and holds moisture.
• Autumn (Sep–Oct): ease off to fortnightly. Keep height moderate; let the lawn build reserves before winter.
• Winter (Nov–Feb): only if grass is actively growing in a mild spell, blade set high, dry day, take just the tips off. Most weeks: skip.

When not to mow

• The grass is wet from rain, dew, or watering. Wet blades tear instead of cut, the clippings clog the deck, and you'll leave wheel ruts.
• There's frost on the leaves — the brittle blades shatter under the mower and brown patches follow.
• Soil is sodden after heavy rain — you'll compact it and leave deep tyre marks that are hard to fix.
• A heatwave with no irrigation. The lawn is stressed; cutting adds more stress. Wait for cooler weather or rain.
• You've fed in the last 24 hours. Let the granules wash in first.
• You've seeded in the last 6–8 weeks. New grass is too tender; wait until it's been mowed once at a higher setting before going to your normal height.

How to do it

1. Walk the lawn first. Pick up sticks, stones, dog toys, anything the blade could chuck out. Spotting molehills now saves a clogged deck later.
2. Set the height. Typical guidance for utility lawns is around 25 mm in summer and 40 mm in spring, autumn, and winter — taller heights for cooler months, shorter in active growth. In a hot dry spell, raising the cut to ~40 mm even in summer shades the soil and conserves moisture; that's a defensive adjustment, not the baseline. If you're not sure, err high — you can always go shorter, but you can't un-scalp.
3. Check the blade. A sharp blade slices; a dull one tears. Tearing leaves frayed leaf tips that brown the next day. Sharpen at the start of the season and after any encounter with a stone.
4. Mow in a different direction each time. Up–down one week, diagonal the next, side-to-side after that. This stops the grass leaning and growing into "ridges".
5. Take it slow. A pace where the mower can comfortably keep up. Rushing leaves uncut tufts.
6. Decide: collect or mulch? Mulching (leaving clippings on the lawn) recycles nitrogen back into the soil. Works well when you mow often enough that clippings are short. Collecting is necessary if you've let the grass get long, or if it's wet.
7. Edges and awkward corners. Walk-behind mowers miss the strip against fences and walls. A handheld trimmer or shears finishes the job.

What to expect afterwards

A healthy lawn looks slightly "pulled forward" right after a cut — the leaves all leaning the way the wheels rolled. That settles within a day. By two days post-cut, you should see no browning, no ragged tips, no scalped patches. The colour might look a touch lighter for a day, then deepens as the leaves orient themselves to the sun again.

If you see straw-coloured tips a day later, the blade is dull — sharpen before next time.

If you see yellow-bordered patches, you went too short. Skip a week, raise the height, and let it grow back.

Common mistakes

• The Saturday-afternoon scalp. Letting grass grow tall over a week or fortnight, then cutting it all the way down in one go. The grass yellows for two weeks afterwards. If it's already long, cut just the top third, wait three days, cut again.
• Mowing wet to "tidy it up before guests arrive". It looks worse than not mowing — uneven, clumped, with wheel marks.
• Same direction every time. The lawn develops a permanent "lean" and dense ridges where the wheels track.
• Leaving the blade dull all season. A sharp blade slices; a dull one tears. The frayed leaf tips brown the next day, leaving the whole lawn with a faint straw cast. A seasonal sharpen takes minutes and shows in the next cut.
• Stripes obsession on a beginner lawn. Stripes come from a rear roller and mature, dense turf. Worry about them when you've nailed the basics.

Seasonal notes

Spring: don't rush the first cut. Wait until the grass has been growing for a week or two. Set the blade high — you're encouraging new growth, not punishing winter laziness.

Summer drought: if the lawn turns brown and crispy in July, lay off mowing entirely until rain returns. The lawn isn't dying — it's dormant. Mowing dormant grass damages the crown.

Autumn: the last cut of the year. Time it for a dry week in late October or early November when growth has clearly stopped. Take the height down a touch — too long over winter invites disease.

Winter: the rare mid-winter trim only. Pick a dry, frost-free morning. Blade high. In and out.

What kit makes mowing easier?

A reliable mower and a balanced summer feed do most of the heavy lifting here: a clean cut keeps the lawn dense, and the right feed gives it the energy to recover between cuts.

Related Mowd guides: UK Lawn Care Calendar · How to water your lawn effectively

Frequently asked questions

How short should I cut my lawn?

For a typical UK family lawn, around 25 mm in summer and 35–40 mm in spring, autumn and winter. Never remove more than a third of the leaf in one cut.

How often should I mow?

Weekly through the growing season (March to October), or twice a week in peak summer if you feed and water. Ease off to fortnightly in autumn and skip most weeks in winter.

Should I mow wet grass?

Avoid it. Wet blades tear rather than slice, clippings clog the deck, and the wheels can leave ruts. Wait until the lawn has dried.

Disclaimer

This is a general guide for typical UK domestic lawns. It doesn't cover every grass mix, every soil type, every climate quirk, every mower, or every special-case lawn (sports turf, ornamental fine turf, very large estates). If your lawn behaves unexpectedly after following this advice — or if it's been struggling for reasons you can't pin down — talk to a local lawn care professional who can see it in person.