Get your lawn in shape before winter

The nights are closing in, and gardeners across the nation are putting away their lawn mowers until spring. But what should you do to protect your mower while it's out of use?

Not taking the proper care when putting your lawn mower away over winter can be a costly mistake – you might find that when you come to use it again, it won't wake from its hibernation, and you'll be forced to invest in a replacement. 

Similarly, there are some things you can do to keep your grass in the best possible shape as the chilly winds of winter make their presence felt, so that you'll have a healthy and lush lawn come spring.

We've put together six essential steps to bear in mind when packing up your lawn mower and looking after your grass for the winter months.

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1. The last cut of the season

As the days grow colder and shorter, your grass's growth will become slower. Generally, you'll want to mow your lawn for the last time of the year in late autumn, when you start to see the temperature regularly dip below 10°C. 

Aim to cut your grass fairly short on this final mow. In winter, the grass is more susceptible to lawn diseases and fungi, and long, damp blades of grass can harbour those diseases. Do remember the 'one-third' rule though - never cut more than one third of the grass blade length at a time. Cutting more than this can put stress on the grass, making it less robust. 

It's best to mow when the grass is dry to achieve a clean cut. Wet grass can be more challenging to cut evenly and may result in clumps of clippings that can smother the lawn. You also need to be sure to avoid cutting the lawn when it's frosty, as this will damage both your mower and the grass itself.

Clear autumn leaves from your lawn with one of our best buy leaf blowers.

2. Give your mower a good clean

Tidying up your mower before you store it away will both protect it and keep it looking fresh.

Brush away mud, leaves and grass – this will help to slow the build-up of rust on the mower, and prevent key components like wheels and grass catchers from getting clogged up and stiff.

Before you tip the mower on its side to clean underneath, make sure it's switched off and has no source of power that can be accidentally triggered. When you tip a petrol mower, make sure the air filter is on top – otherwise, you risk oil running into the filter. 

For tricky-to-reach nooks and crannies, and especially on the blades, use a stiff brush or stick to remove the debris – don't use your hands. We'd also suggest not using a hose either; although it can get the job done quickly, you run the risk of damaging any electrical components, and you'd have to make sure it was completely dry before storing to avoid rust. 

It's not the most glamorous job, but it does have to be done to keep the mower running efficiently - and it will be far more unappealing to do in spring. Wouldn't you rather clean off grass and mud that isn't six months old?

Make sure you get a mower that performs by comparing our lawn mower reviews.

3. Petrol mower owners - drain or treat your fuel, and replace your oil

Only petrol lawn mowers are powered by fuel that needs topping up, so cordless and electric mower owners can skip this step.

It's unlikely that the mower's fuel tank will be completely empty after its last use before being tucked away for winter. Leaving fuel in the tank for that long is risky because after around 30 days, it can start to degrade and become stale. After a few months, there's a pretty good chance the engine will be clogged and struggle to run.

Draining the tank is the safest option, but you'll need a siphon hose to do this effectively. You can buy cheap ones for less than £10.

There are also some stabilising liquids you can buy that keep your fuel fresh until the mower is ready to be used again. Most claim to extend the life of fuel by around two years. Do your research and shop around before buying one of these, though, as there are a lot of options out there and some will work better than others.

With oil, you should do the opposite: at the end of the season, remove all the old oil and fill up with fresh oil. Storing a mower with old oil in it can allow nasty deposits to settle at the bottom, which will damage the engine when you go to start it up again in spring. 

Ready to pick a lawn mower that will last? Compare the best lawn mower brands.

4. Cordless mower owners - remove the battery

If you own a cordless lawn mower, you need to be mindful of how to treat the mower's battery in the off-season.

Keeping your batteries in good nick is very important, as replacement ones sometimes cost as much as the rest of the mower. Batteries don't like any environment that's too cold, hot or damp. A cool dry place is perfect, so find an appropriate spot indoors where you can store it over winter. Remember, most sheds aren't frost-proof.

While you're at it, give the battery itself and the battery terminal on the mower a good clean with a dry cloth. Don't use water, as it could harm the electronics and prove dangerous. 

Even though you won't be using your battery during the off-season, you should still give it a charge a few times. If you let the battery run out completely and it remains at zero-percent charge, it might not hold a charge at all when you go to use it again.

Compare our cordless lawn mower reviews.

5. Store in the right spot

Leaving  your mower outside will invite rust to set in, putting your mower at risk of never cutting another blade of grass. 

A shed or garage are good options, but be wary of damp, though. Wooden sheds in particular offer poor protection from moisture build-up. Keep your mower away from any appliances or active devices that heat up, as this can be a safety risk. Collapse the handles (if you can) and remove the grass collector to save room. If you have a corded mower, be wary of how tightly you wind the cable before storage. By all means tidy it away, but don't put undue strain on it, or it might fray or break.

Consult the manual before storing a petrol mower vertically – some have special features to allow storage this way, but if yours doesn't, you may run the risk of oil and fuel seeping into the engine. You don't need to be a mechanic to know that this is something you should avoid. 

Not everybody has a shed or space to store their lawn mower indoors. So if you have to keep it outside, cover it with a waterproof tarpaulin.

Find a home for your mower with our guide on how to buy the best shed.

6. Treating your lawn for healthy grass and preventing moss

The mower's tucked away, but unfortunately, there's still some yardwork that needs doing. Over winter, when the grass is wet and the skies are dark, moss can thrive. And though it might look nice and green in the winter, once we swing back around to summer you'll find some unappealing brown patches in your garden. 

The best way to discourage moss is to encourage the grass. Before the ground gets really cold, and while the soil is still soft, aerate your lawn to allow air, water and nutrients to reach the roots. You should also use a lawn feeds to help growth, as these give your grass essential nutrients during the dormant period, and promote strong root growth and better overall lawn health. 

If you do find moss beginning to grow, consider using a mosskiller. These should make quick work of the unwanted moss and help restore the health and appearance of your lawn. Choose a mosskiller specifically formulated for lawns, as they are designed to target moss without harming your grass. Once the moss has turned black and died, you'll need to rake it away so it doesn't hinder the growth of the lawn. 

Check out our guides to the best lawn treatments, and on how to get rid of moss in a lawn.