What size lawn mower do I need?

When the weather turns nice, you’ll want to get out and enjoy your garden. As that will probably mean you’ll have to give the grass a trim first, the last thing you need is to dread getting out your lawn mower. If your mower is too light, it won’t be able to do the job properly. If you’ve got one that’s too heavy, you’ll struggle to push it around. Either way, the wrong size mower makes the job so much harder.

But how do you choose the right size? Let our experts talk you through your options with this handy lawn mower size guide.

How big is your lawn?

Chris Cooper, of lawn mower manufacturer Hayter, advises choosing a mower to suit the size of your garden. So, the first thing to do is determine the size of your lawn. Work out the square footage and make a note of that when you start looking at mowers.

You don’t need to be super-accurate – don’t bother buying a special, extra-long tape measure or anything. And don’t stress if the garden is an odd shape, or has separate areas. You can divide the space into sections if that makes it easier, then just pace it out for a rough estimate. All you need is an approximate number so you don’t end up buying a mower that cuts out on you when you’ve only made it halfway round.

You should also consider the layout of the garden. If it’s a long garden, will a power cable be able to reach all the way to the end? If it has lots of steps or tight corners, do you need a mower that’s manoeuvrable enough to handle it? Will you be able to get the mower out of the shed, garage or wherever you’re storing it, with ease?

What types of lawn mowers are there?

Your first decision is to choose between corded or cordless mowers.

If you don’t mind plugging into an electrical socket and running a cable across your garden while you mow it, choose the best corded lawn mower for your garden.

If you prefer to roam free, look for the best cordless lawn mower. Cordless mowers come in two main varieties: electric models which run on rechargeable batteries, or petrol-powered mowers that use a small petrol engine.

Alternatively, if your lawn is flat and you don’t mind a bit of a workout, you could always opt for a manual mower and save on electricity bills. One of the more modern options is a robot lawn mower, which will do all the hard work for you but has a few drawbacks – such as a much higher price tag.

Hayter’s Chris Cooper sums up the choice: “Cordless battery mowers offer flexibility and freedom”, he says, while “corded models ensure continuous power but need a nearby socket.”

How to choose the mower size for your lawn

Paul Hicks, product manager at Stihl, recommends a petrol mower – or even a robot mower – for anything around 600 square metres or larger. If you don’t want to have to mow too often, the more powerful engine will be able to deal with denser grass or longer growth, so you can leave it for longer between mowing.

For anything smaller than 600 square metres, a battery-powered or electric mower will do the job.

As Chris Cooper points out, a smaller mower is generally lighter and more manoeuvrable. And a lighter model is more easily carried, which is handy if your outdoor space has tight corners, odd-shaped areas or lots of steps to deal with.

Also consider the size of the mower’s cutting area. A mower with a wider cutting deck and bigger blade – typically up to around 50cm – will cut more grass on each pass. Claire Baglin, landscaping category manager at Toolstation, breaks down the cutting widths available:

Smaller lawns (up to 300 square metres): “Get a mower with a cutting width of 12 to 17in (30 to 43cm). Mains-powered and battery mowers are suitable for smaller gardens.”

Medium lawns (300-600 square metres): “Get a mower with a wider cutting width of 17 to 19in (43 to 48cm). Cordless electric, robotic and petrol mowers will suit medium-to-large gardens.”

Larger lawns (600 square metres and above): “A mower with a cutting width of 20 to 22in (51 to 56cm) should be used. Ride-on mowers are perfect for extra-large lawns.”

Recommended lawn mowers for small and large gardens

Our recommendation for a small garden is the Bosch CityMower 18, a great all-rounder.

For more corded and cordless options, check out our guide to the best mowers for small gardens.

Our recommendation for a large garden is the Honda Izy HRG 466 PK, a highly capable petrol-engined mower.

For more corded, cordless and petrol recommendations, check out our guide to the best mowers for different sizes of garden.

Other features to consider

Adjustable cutting heights

“Buying a mower with adjustable cutting heights allows you to be in control over how long you want your grass”, explains Claire Baglin. “If you’re mowing wet grass, you’ll want to start with a higher cutting height, because it’s tougher and clumps up more than dry grass.” Check how easy it is to change the height – some mowers just have a handy lever, but others require you to fiddle about underneath, changing the blade with a spanner.

Grass disposal

Chris Cooper highlights a couple of different options for getting rid of grass as you cut: a mulching mower chops up the grass cuttings and spreads them across the lawn to recycle nutrients back into the surface, while a side-discharging mower blows the cuttings out of the side, across the lawn, for a similar hit of garden goodness.

Grass box capacity

If you want to remove the cuttings, for disposal or for composting, a grass box on the mower collects the cut grass instead of spitting it back onto the lawn. As Claire Baglin points out, a larger grass box will mean you won’t need to empty it as often.

Ease of use

Stihl’s Paul Hicks highlights convenient features like handlebars which can be adjusted to different heights, or folded away for storage.

Value for money

Of course, for many people this will all come down to their budget. A petrol mower may be the most reliable and powerful option, but it costs a lot more up-front and has ongoing costs for petrol, oil and maintenance.

Luckily, the right mower doesn’t have to break the bank. “For excellent value, you can’t beat an electric mower”, advises Stihl’s Paul Hicks.