How to clean a lawn mower - A step-by-step guide to keep your lawn mower (and your lawn) in tip-top condition

Wondering how to clean a lawn mower? We ask the experts for their tips to keep yours in good working order

A close up of a red lawn mower mowing a lawn
(Image credit: Getty)

Let’s be honest; lawn mowers aren’t cheap. But while they’re a worthwhile and necessary investment, it’s important to know how to clean a lawn mower to ensure that you’re getting the most bang for your buck.

Yes, the best lawn mowers can last for decades if you give them the TLC they need, and this will ultimately have a knock-on effect on your garden. With this nifty garden gadget at your disposal, you can take stock of the most important lawn care tips and maintain a lawn mowing calendar. This should leave you with a healthy and luscious lawn all year round.

But it’s safe to say that lawn mowers are put through the wringer on a regular basis. The blades become worn down, they get covered in mud and grass, and the grass collection box can even become mouldy. So, cleaning a lawn mower regularly can keep it in check.

How to clean a lawn mower

‘Now that gardening jobs are in full swing, it is important to make sure you maintain all tools to ensure their longevity,’ explains Nick Ee, product and training manager at BLACK+DECKER.'

'Cleaning a lawnmower is particularly important as it gets the most wear and tear throughout spring and summer. If left and not maintained properly, old grass cuttings and debris can create moisture resulting in rust, which shortens the lawn mower's lifespan and performance.’

So, follow this step-by-step to clean yours.

What you'll need


1. Choose the right time

A close up of a red lawn mower mowing a lawn

(Image credit: Billy Currie/Getty Images)

When was the last time you cleaned your lawn mower? If you can’t remember, it’s definitely time to add it to your to-do list. After all, it’s important to clean your garden tools on a regular basis.

The best time to clean your lawn mower is immediately after you’ve used it and before the grass dries. During this cleaning session, simply brushing away the grass clippings from the underside of the lawn mower should be enough.

However, experts suggest giving your lawn mower a deeper clean after around 25 hours of use or at least once a year. You should also aim to sharpen your lawn mower blades once a year, too.

2. Turn your lawn mower on its side (if possible)

The first step when cleaning a lawn mower is understanding the lawn mower you own. Jim Kirkwood, garden expert at Worx, ‘Depending on the type of mower you own, the cleaning process may look a little different, and you should always check your manufacturer’s instructions before starting.’

Ideally, you should then turn your lawn mower on its side. However, it’s important to note that you should NEVER turn a petrol lawn mower on its side while there is still petrol in the tank. Either empty the tank and remove the spark plug first or skip to step 3 for more information.

If you have an electric lawn mower, you can simply turn it off, unplug it completely, remove the grass collection box, and then turn it on its side so that you can see the underside of the lawn mower.

If you have a battery-powered lawn mower, all you have to do is remove the grass collection box and the battery before turning it on its side. This is to ensure that it doesn’t accidentally turn on while you’re cleaning it.

3. Clean the underside

underside of lawn mower -GettyImages-1783770814

(Image credit: Traimak_Ivan/Getty Images)

When your lawn mower is on its side, you can then get to work on cleaning away the grass clippings and dirt underneath it.

Jim says, ‘To clean underneath the deck, put on your gloves and wipe away any debris with your plastic brush, taking particular care around the blades. Failure to remove grass from around the motor can cause your mower to overheat.’

If you wanted to, you could then rinse down the underside with a garden hose, using low-pressure water to wash away any leftover debris. In fact, that’s why some lawn mowers - including many petrol lawn mowers - come complete with a hose connection specifically for this cleaning task.

Simon Hill, Service Manager at STIGA UK says, ‘Many of our petrol lawnmowers are equipped with a wash point, enabling you to connect a hose pipe to the machine which will wash the underside of the deck casing and blade. The upper part of the machine can be cleaned with a damp cloth and some detergent, when doing this, it's essential not to get any water on any of the electrical components.’

And if you find that this doesn’t quite do the trick, you could use a mixture of soap and water to clean any stubborn areas. Nick explains, ‘Use a stiff brush or sponge with soapy water to scrub the lawn mower to remove any left-over dirt that could be hiding and make sure to rinse thoroughly afterwards.’

4. Check the cutting blades

lawn mower cutting stripes in grass - GettyImages-170168600

(Image credit: wwing/Getty Images)

No lawn mower would be complete without the cutting blades, which is why you should check them throughout the year. Failure to do so could lead to insufficient mowing and even patchy grass.

‘To clean the blades, simply wipe them down with your dry cloth to remove any excess grass clippings that have built up,’ explains Jim.

But that’s not all. You should also keep an eye out for any blade dullness or wear and tear, as you may need to give your lawn mower blades some extra TLC, too.

Claire Baglin from Toolstation says, ‘A dull lawn mower blade can actually damage a lawn. Rather than cleanly slicing the grass tips, a dull blade can cause rough cuts that can tear the grass sods out of the ground completely, creating bald patches.’

‘There are three tell-tale signs that mower blades need sharpening: Dents or nicks on the blade surface, uneven grass height after cutting, and brown, frayed grass edges.’

In this instance, you should sharpen your lawn mower blades with something like this SHARPAL 103N All-in-1 Knife and Garden Tool Blade Sharpener from Amazon. But it’s important to make sure that sharpening is the right option.

Claire says, ‘If there is any damage beyond slight dents or scratches, it’s best practice to replace the blades.’

5. Clean the grass collection box

When you’ve cleaned the underside of your lawn mower, you can then turn your attention to the grass collection box. If left untouched, the build-up of grass clippings can result in mould and grime. So, it’s best to empty it after every use and then give it a deeper clean every once in a while.

The easiest way to do this is to brush away any large clumps of grass clippings and then use a garden hose to rinse it out. Then, dry it with a microfibre cloth before placing it back on the lawn mower.

Don’t be tempted to swap the garden hose for one of the best pressure washers, though. Your lawn mower is one of the many things you should never clean with a pressure washer.

6. Give it another once-over

red lawn mower in large garden - GettyImages-85636383

(Image credit: Jupiter Images/Getty Images)

To finish, give the whole lawn mower another once-over. Jim says, ‘Whilst the mower is on its side, check the wheel bearings for any trapped grass that may slow it down. Once finished, place the mower in its upright position and clean the exterior with your cloth’

With the brush, brush off any loose grass clippings, dried dirt, or pollen, and then use a wet microfibre cloth to wipe the whole thing down.

‘Once fully clean, be sure to store your lawn mower in a dry and protected place such as your garage or a garden shed,’ adds Jim.


How should I clean my lawn mower?

Before cleaning your lawn mower, you need to make sure that it’s either turned off at the mains, the battery is removed, or the petrol tank is empty. Then, turn it on its side and brush the underside of the lawn mower.

Aim to remove all of the grass clippings from the blades and the deck, and give the blades a once-over while you’re there. It may be that you need to sharpen your blades or replace them entirely.

You can then brush grass clippings out of the grass collection box before rinsing with a hose. Finish by wiping down the exterior of the lawn mower with a brush and a wet cloth.

Is it okay to hose down a lawn mower?

While you can hose down certain elements of a lawn mower - such as the grass collection box and deck - it’s not advisable to hose down a lawn mower completely. This could cause serious damage.

So, always check the manufacturer’s instructions before using a hose on a lawn mower.

Now you know how to clean a lawn mower, you have no excuses!

Lauren Bradbury

Lauren Bradbury is a freelance writer and major homes enthusiast. She graduated with a Bachelor’s degree in English and Creative Writing from the University of Chichester in 2016, before dipping her toe into the world of content writing. After years of agency work, writing everything from real-life stories to holiday round-ups, she decided to take the plunge and become a full-time freelancer in the online magazine world. Since then, she has become a regular contributor for Real Homes and Ideal Home, and become even more obsessed with everything interior and garden related. As a result, she’s in the process of transforming her old Victorian terraced house into an eclectic and modern home that hits visitors with personality as soon as they walk through the door.