Prepare Your Lawn for the Cold Months
The final mow is your last chance to set your lawn up for winter. Our Winter Lawn Treatment hardens grass against frost, strengthens roots, and keeps colour through the darkest months.
The last mow of the year matters more than most people think. Get the timing and technique right, and your lawn enters winter in the best possible condition. Get it wrong – mow too late, too short, or skip it entirely – and you’ll spend spring dealing with the consequences.
Here’s when to make that final cut, how to do it properly, and what to do with your mower before storing it away.
When to Do the Last Mow
There’s no fixed date – it depends on when grass stops growing. In the UK, this is typically somewhere between late October and mid-November, though mild autumns can push it later.
Watch for these signs:
– Growth has slowed dramatically (mowing needed every 2-3 weeks instead of weekly)
– Daytime temperatures regularly below 10°C
– First frosts arriving
– Grass is still just about growing, but only just
The goal is to mow while the grass is still active enough to recover slightly before going dormant. Mowing frozen or dormant grass damages it without any benefit.
Don’t mow if:
X Ground is frozen
X Heavy frost is on the grass (wait until it thaws)
X Lawn is waterlogged
X Grass has completely stopped growing
Why the Final Mow Matters
Grass that goes into winter too long is vulnerable to problems:
X Snow and frost flatten long grass, creating dead patches
X Fungal diseases thrive under matted, damp grass
X Pests find shelter in longer growth
X The lawn looks untidy all winter
But grass that’s cut too short is also vulnerable:
X Less leaf means less photosynthesis during winter’s limited sunlight
X Shallow roots from close cutting dry out faster in cold winds
X The crown of the plant (its growing point) is less protected
The ideal final mowing height balances these concerns – short enough to avoid problems, long enough to protect the plant.
How to Do the Final Mow
Clear leaves first
Fallen leaves are the biggest issue in late autumn. Rake or blow them off the lawn before mowing. Leaves left on the grass block light, trap moisture, and create perfect conditions for fungal disease and moss.
If you mow over leaves, you’ll just chop them up and push them into the grass – which isn’t much better than leaving them whole.
Set the height correctly
Raise your mowing height slightly for the final cut – around 4cm is ideal for most lawns. This is higher than summer mowing but not so long that it causes problems.
The one-third rule still applies: if the grass is currently 6cm, cutting to 4cm is fine. If it’s grown much longer, consider a first pass at a higher setting before the final cut.
Choose a dry day
Late autumn weather is often wet, but try to mow when the grass is dry. Wet grass clumps, cuts unevenly, and can spread disease. A dry spell after frost has cleared is ideal.
Collect the clippings
For the last mow, collect the clippings rather than mulching. Decomposition slows dramatically in cold weather, so clippings left on the surface will just sit there creating a soggy layer. Better to remove them and let the lawn breathe.
After the Final Mow
With the mowing done, there are a few more tasks to complete before winter truly arrives.
Apply winter feed
If you haven’t already, now is the time for winter lawn treatment. Winter feeds are high in potassium and iron, which harden the grass against frost and disease without promoting soft growth that would be damaged by cold.
Apply within a week or two of the final mow, while the grass can still take up nutrients.
Continue clearing leaves
Trees keep dropping leaves well after your last mow. Check the lawn weekly and remove any accumulation. A thick layer of leaves over winter is one of the main causes of moss and bare patches in spring.
Address any drainage issues
If parts of your lawn stay wet for days after rain, consider aeration now (if the ground isn’t frozen) or make a note to address it in spring. Waterlogged grass over winter is prone to disease and moss.
Storing Your Mower
Your mower will sit unused for several months. A few minutes of preparation now prevents problems in spring.
Clean it thoroughly
Remove all grass clippings from the deck, blade housing, and collection box. Built-up grass holds moisture and promotes rust. A stiff brush and hose (for robust mowers) or dry cloth (for electric models) works well.
Check and sharpen the blade
Inspect the blade for damage. Either sharpen it now or make a note to do it before the first mow of spring. A sharp blade makes all the difference to cut quality.
Deal with fuel (petrol mowers)
Old fuel goes stale and can gum up the carburettor. Either run the mower until the tank is empty, or add fuel stabiliser if you’re leaving fuel in over winter. Check your manual for specific recommendations.
Charge the battery (cordless mowers)
Store lithium batteries partially charged (around 50%) in a frost-free location. Don’t leave them fully charged or fully depleted for months – both reduce battery lifespan.
Store properly
Keep the mower in a dry place – shed, garage, or covered area. Moisture causes rust and electrical problems. If your storage area is damp, consider a mower cover.
What If You Miss the Window?
If you’ve missed the ideal time and the grass has gone dormant or frost has set in, don’t mow. It’s better to leave the lawn longer than to damage frozen grass.
During mild spells in winter, grass sometimes puts on a bit of growth. If this happens and the lawn looks untidy, a light trim on a dry day is fine – but keep the height at 4cm or above and only mow if the grass is genuinely growing, not just looking long. For more on managing your lawn through the colder months, see our winter lawn care guide.
Frequently Asked Questions
What month should the last mow be?
Typically late October to mid-November in the UK, depending on the weather. Watch the grass rather than the calendar – mow when growth has slowed dramatically but hasn’t completely stopped.
How short should the final cut be?
Around 4cm – slightly longer than summer mowing height. This protects the grass through winter while avoiding the problems of leaving it too long.
Should I fertilise before or after the last mow?
Either works, but applying winter feed after the final mow is often more practical. The lawn looks tidy, and the feed can work its way down without being disturbed by mowing.
Can I mow if there’s been a frost?
Wait until the frost has completely thawed and the grass is dry. Mowing frozen grass damages the blades and compacts wet soil. Late morning or afternoon on a dry day after frost is best.
What if my lawn is still growing in December?
Mild winters can extend growth. If the grass is genuinely growing (not just looking long), a light trim on a dry, frost-free day is fine. Keep the height at 4cm or above.
For more mowing guides and seasonal lawn advice, explore our complete lawn care hub.
Setting your lawn up for winter? Our Winter Lawn Treatment hardens grass against frost, strengthens roots, and maintains colour through the coldest months – the final piece of your autumn lawn care.
