How to maintain your mower and cut the perfect lawn

The lawn takes centre stage in most gardens. When your lawn looks good, the whole garden looks good – but there are a couple of tricks that make things a little bit easier. Our expert guide explains how to cut the perfect lawn.

To help you keep your garden looking its best throughout the year, we've pulled together some top tips on how to cut your grass, making sure to explain the ideal height for your mower blades and how often you need to repeat the process.

Keep scrolling and you'll also spot our handy lawn care checklist, split by season so you know what you need to do whether it's a toasty summer or a chilly winter.

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How to cut the grass

Step 1: Check your lawn

Before you start mowing, have a look around the garden and pick up any loose pebbles or small sticks. Without doing so, you risk debris striking your mower blades, which could damage the machine and cause injury if the materials are propelled back out.

If the grass is wet, consider waiting until it's dry.

Step 2: Safety checks

If you're using a corded mower, place the cable over your shoulder to avoid cutting through it. Always make sure it's connected to an RCD (residual current device) to prevent electrocution.

Choose appropriate footwear: sandals and flip flops don't offer enough protection; steel-toe boots are the best for protecting your toes from serious injury. You might also want to wear eye protection in case stones fly up and a pair of sturdy gardening gloves.

Step 3: Cut around the edge of the lawn

Now you're ready to begin cutting. We suggest you start by cutting around the edge of your lawn, taking care not to snag any plants you might have at the side of your garden.

When you're mowing the sides of your lawn, try to avoid standing on the edge (where the grass meets your flowerbed) as this can damage the edge.

Shopping for a new lawn mower this year? Before you part with your money, have a read through our guide on the best lawn mowers.

Step 4: Continue cutting in lengths

Cut up and down the full length of your lawn, overlapping the previous strip each time so you don't miss any spots.

Empty the collection box regularly or it may drop clumps of clippings on the lawn.

Step 5: Finishing touches

Finally, you can cut the edges of your lawn with shears or a grass trimmer for a neat result.

To see which lawn finishing tools have impressed in our rigorous lab tests, see our grass trimmer and strimmer reviews.

What height should the lawn mower blades be?

The height of the blades on most mowers can be easily adjusted using a lever, although on some hover mowers you'll need to add or remove spacers, which is a bit more fiddly. 

At the start of the mowing season in spring, set the blades high then gradually lower them over the weeks, until you reach the main cutting height of 25mm. Cutting lower than this can result in a lawn that's weakened and more susceptible to drought and other problems. 

For luxury lawns that don't get used much, you can cut as low as 12mm in summer.

How to get stripes in your lawn

To get stripes when you mow, you'll need a lawn mower with a roller; this will squash the grass flat after the mower cuts it. Hover mowers never have rollers, but most other types of mowers can have rollers, although it depends on the individual model. 

When cutting stripes, it's important to mow up and down the lawn to get the neat effect you want. The stripes are created by the light reflecting off the grass blades. Grass facing towards you looks dark, while grass facing away from you looks light. The contrast of the two creates the stripes.

Longer grass creates the best effect as the grass blades bend further than shorter grass, and heavier mowers tend to leave the best stripes. 

Check out the Best lawn mowers with rollers to get a striped lawn

Can you cut wet grass?

It's best to cut the grass when it's dry. Wet grass clippings are harder for the mower to pick up and you're likely to get lumps of clippings left on the lawn. For every lawn mower that we test, we check how well the machine cuts wet grass. 

One thing you should certainly avoid is cutting frosty grass. This is a sure-fire way to damage the grass, and can leave marks where you've been.

To see which models are the best for cutting in damp conditions, check our expert lawn mower reviews.

What to do with lawn clippings

Some mowers offer a mulching function that cuts up clippings and pushes them back into the turf so you don't need to pick them up.

Discover the best lawn mowers that mulch clippings

Most lawn mowers have a collection bag or box that fills with clippings as you mow. Many have an indicator so that you can easily check how full the bag is and whether it needs to be emptied. When testing lawn mowers, we mark them for how well each model fills its grass-collection bag.

You can put grass clippings in your green-waste collection bin, although if you've used weedkiller on the lawn you usually have to cut it a certain number of times before the cuttings are safe to put in the compost bin. This will be stated on the weedkiller's label.

You can also compost your grass clippings. It's best to either add leaves from deciduous trees (at a ratio of one part leaves to one part grass clippings), or to add soil at the same ratio. Both methods absorb the liquid in grass clippings and prevent them from turning slimy.

If you're left with a lot of grass clippings, why not compost them? Here out guide to how to make compost

When to cut grass

In the growing season between spring and early autumn, your lawn will be growing strongly and should be cut every week or even twice a week if possible. This will stop it from growing too long and keeps clippings to a minimum.

In winter, grass only needs cutting very occasionally if there's been a mild spell of weather and it's grown again.

Spring and summer lawn care

Grass gets a lot of wear over the warmer months, so make sure your lawn is in top condition. 

• Feed the grass – the secret to greener grass is to feed your lawn. 
• Kill lawn weeds – unless you like certain weeds, such as daisies. If so, either spray carefully with a lawn spot weed killer or dig out the weeds you want to remove with a daisy grubber. Low-growing spreading weeds, such as clover, can be difficult to kill. Try raking them before you mow to raise their stems and you’ll weaken the plants over time.
• Prevent moss – shade from surrounding plants and trees is a common cause, so try to reduce this if possible by thinning out growth. Feeding the lawn and reducing compaction by spiking the surface with a garden fork should also help.
• Repair bumps and hollows – use a spade to cut a H-shape in the grass and peel back the turf so you get two flaps. Then either add or remove soil to make it level. Put back the turf, firm it down and keep it well watered. 

Discover the best lawn treatments

• Relieve grass compaction – poor drainage and a collection of rain water beneath the surface means the grass roots struggle to get oxygen and the grass fails to grow. Get air back into the soil by pushing in a garden fork every 20cm or so.
• Repair bare patches in the lawn – remove the cause of wear, then either use a shop kit to fill the patches or rake the area yourself, sow grass seed and cover with compost or soil.

Autumn lawn care

Getting your lawn in shape after a busy summer of heavy usage is well worth the effort. 

• Kill moss – apply a moss killer, remove sources of shade and relieve compaction in the turf.
• Rake or scarify – this process will open up the sward and make space for the new grass plants to grow with less competition.
• Oversow – sowing grass seeds onto existing turf will help thicken it up and prevent weeds filling the gaps. 
• Top-dress – it will help improve soil quality. Mix three parts sharp sand with one part of bought compost. Apply at 2kg per sq m and work into the turf with a brush. Don't mow the grass for two or three weeks afterwards. 
• Water and feed if needed – ensure the lawn is kept, don't saturate. You can also apply an autumn feed to strengthen the turf before winter.

Winter lawn care

The best strategy is normally to leave the lawn alone during winter, but there are some jobs that are good to do.

• Mow as needed – in our changeable climate, we can often see significant growth during mild winters. Mow the lawn as required, when the turf isn't wet or frosty.
• Watch out for fungal diseases – fungal spores live in soil and will cause turf diseases when it's damp and humid. A good preventative method is to brush off morning dew from the grass.
• Don't walk on frosty grass – it can damage it. The same applies during very wet weather.

Protect your hands with our Best Buy garden gloves

Lawn mower repair and maintenance

Replacement parts for lawn mowers

One thing to consider before buying any type of lawn mower is how easy it will be to get replacement parts if you encounter any issues.

You can expect most mowers to last a decent amount of time (at least seven years or more) but that doesn't mean you'll never need spare blades, springs, or perhaps a replacement mower belt.

Most major mower retailers such as Bosch, Cobra, Flymo, Ryobi and Stihl offer spare parts for their lawn mowers, either directly from their website or through a third-party seller.

It's always worth checking on the availability of spare parts before you commit to a purchase, as you don't want a minor fault to end up in you replacing your entire mower because you can't get hold of a certain part.

With cordless mowers specifically, you should check to make sure it's possible to buy replacement batteries separately. We don't give Best Buys to models where the batteries can't be replaced, so will never recommend a mower that's destined to have an unusually short lifespan.

How to service a petrol mower

A local-garden machinery specialist should be able to service and repair your mower, especially petrol models, so always check before you discard a mower that seems to be broken. A lawn mower service will cover various components including spark plugs, air filters, blades and oil.

If you're servicing your petrol mower yourself, your best port of call is to first consult your lawn mower’s manual. It may give an indication of how often to change the oil, so check there, but a good rule of thumb is to either change it at the start of each mowing season or after 50 hours of use – whichever comes first. Regular checks with a dipstick, just like you would on a car, will also ensure that you’ve used the right amount. And whilst you’re changing or checking the oil, check the air filter and spark plugs, too. These are both pretty easy to clean to ensure your mower can turn over and run, but you should also keep in mind that, like oil, they should be replaced annually to help your lawn mower work as efficiently as possible.

How to service an electric mower

Cordless mowers quite literally live and die by their batteries, and it’s imperative that you take proper care of them. The lithium-ion battery that you’ll find inside your mower is sensitive to extremes of temperature, which will damage the cells or reduce the performance. It’s best to store the battery indoors – and keep it away from any blisteringly hot greenhouses or sheds. 

In the off season, you should make sure that you charge your battery up a few times, even though you’re not using it. If you allow the battery to deplete and stay at 0% charge, it may subsequently fail to hold any charge at all when you come to use it again. If the battery does permanently die, you should be able to use a replacement to get the mower up and running again, although you may be surprised at the price. In line with this, you should never buy a cordless mower with a battery that cannot be replaced or removed. 

As for corded mowers, our main piece of advice is to ensure that your power cord is in good working order. Any visible damage is a point of potential danger, and the mower should not be used until the cord is replaced or repaired in line with the safety instructions detailed in the user manual.

How to sharpen mower blades

For the best performance you’re going to want to keep the blade nice and sharp. A dull blade is a nightmare to cut with, and it can damage your lawn. If the blade isn’t sharp enough, it will rip at the grass rather than cut it, giving a patchy finish. 

Once you’ve finished mowing, take a look at your lawn. If it looks rough and uneven, that’s a good indication that your blades need sharpening.

If you're planning on sharpening your mower blades yourself, take extreme care – you'll need protective eyewear, earplugs and gloves.

Make sure your mower is powered off before you proceed. Note that, if the blade is extremely damaged, it will need replacing entirely.

Using an angle grinder, work along the blade slowly. Your mower blade has a natural angle to it, so make sure to follow that with your angle grinder closely as you don't want to dramatically change the shape of the blade.

How to clear out the undercarriage

Every time you cut your lawn your lawn mower’s undercarriage is going to become clogged and dirtied by grass cuttings and debris. This will negatively impact performance and can even cause the spread of lawn diseases. Ideally, you should clean your lawn mower after each session - especially if you’re cutting wet grass - but failing that, try to clean it at least every month. Use a wire brush, damp cloth or air line to scrape and spray away any debris clinging to your lawn mower’s deck. 

Some petrol models even have a ‘washout port’ which a hose is plugged directly into to wash out debris, but we wouldn't recommend you use your garden hose on any electric mowers as you're then running the risk of water getting in to and damaging the electronic components.

If you tip your mower on its side to clean it, make sure you have the air filter on the top so that no oil leaks into it. 

Check out our guide on which lawn mower brand to buy to find out about the most durable lawn mowers.