Mulching mowers have a mulching function that chops grass clippings into tiny pieces, which are then recycled back onto the lawn as a natural fertiliser.
In the UK, there are dedicated mulching mowers, as well as mowers that have an optional mulching feature alongside other options, like collection and rear discharge.
Here, I’ve outlined the pros and cons you should be aware of when deciding whether a mulching mower is the best fit for your needs.
✅ Key Takeaways:
The key advantages of mulching lawn mowers are that they’re great for grass health, they eliminate the hassle of emptying the grass box, they reduce grass cutting time, they offer an environmentally-friendly alternative to using chemical fertilisers, and they can also be used for mulching leaves.
The disadvantages of mulching mowers are that they’re not suitable for all grass cutting occasions, they won’t leave your lawn looking neat and tidy after mowing, they cost slightly more on average than collection-only mowers, they require a regular mowing schedule, and they’ll limit your choice of mowers because not all mowers have a mulching feature.
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👍 Mulching Lawn Mower Pros
Here are some of the key benefits of mulching mowers compared to other mower types:
🌱 They’re Great For Grass Health
The main benefit of mulching grass with a mulching lawnmower is that you’ll improve your lawn health with no extra effort on your part.
A mower with a mulching blade produces nutrient-rich “mulch” (that’s the tiny grass clippings that are distributed onto your lawn), which increases soil fertility and quality, supporting the microorganisms that live in the soil, improving water retention, and supporting healthy grass growth.
🌟 They Encourage A Nicer-Looking Lawn
A healthier lawn looks greener and grows thicker, so using a mower with a mulching attachment is an easy way to achieve a lawn that’ll be the envy of all your neighbours.
If you spend a lot of time outdoors in the summer or you’re simply garden-proud and care about appearances, you’ll appreciate the aesthetic benefits of mulching lawn mowers.
As long as you mulch regularly and on the right occasions, your lawn should look denser and healthier as a result of your mulching efforts.
📦 They Eliminate The Hassle Of Emptying A Grass Box
Mulching grass also eliminates the hassle of emptying a grass bag or box.
If you struggle to detach and attach your mower’s grass box, you’re not good with heavy lifting, or you just want to mow your lawn as efficiency as possible, you’ll appreciate that mulching is a one-and-done job.
The grass cuttings are deposited back onto your lawn, but, unlike with a rear or side-discharge mower, they’re much smaller than they’d be if they were simply collected in the mower’s box.
That means you also don’t have to worry about raking up the grass cuttings once you’ve finished mowing – so there’s another job you can cross off your list.
⏰ They Reduce Grass Cutting Time
Because mulching saves time, you can cut your grass up to 30% quicker if you use your mower’s mulch function.
You won’t have to routinely stop mowing when the grass bag gets full, and there’s no need to rake or sweep your lawn after mowing.
If you value your time, you want to spend longer enjoying the rare UK sunshine, or you simply don’t enjoy your lawn mowing duties, you’ll enjoy the faster, simpler process that mulching lawn mowers provide.
🍂 They Can Also Mulch Leaves
Grass isn’t the only thing that a mulching lawnmower can mulch. If your lawn has a few trees and bushes that lose their leaves in autumn, you’ll be happy to hear that the best mulching lawn mowers are also capable of mulching leaves.
Leaves provide a further source of valuable nutrients to your lawn, so don’t waste time raking the leaves off your garden before you start mowing – leave your mower to do the hard work.
In fact, mulched leaves are even easier for earthworms and microorganisms to decompose, so they may be even more beneficial to your lawn than the grass cuttings themselves.
♻️ They’re Environmentally Friendly
There are a couple of reasons why mulching lawn mowers are good for the environment.
The mulched grass clippings offer an environmentally-friendly alternative to using chemical fertilisers. Plus, you have no garden waste to dispose of, so you don’t have to feel guilty about wasting resources that could otherwise be recycled.
If you want to limit your environmental impact in every way, every little action counts – and switching to a mulching lawnmower is a great eco-friendly move to begin with.
💰 They Reduce Lawn Care Costs
If you spend too much money on lawn maintenance products for your garden, you’ll be happy to know that using a mulching lawnmower can help you to cut down your spend in this area.
Mulching grass provides a completely free, natural fertiliser that will help your lawn grow healthily without the need for specialized products from your local garden centre.
The organic matter increases the fertility of the soil, improving soil quality without the need for supplementary assistance in the form of a commercial lawn fertiliser – which likely contains chemicals, toxins, and other ingredients that are best staying out of our environment.
👎 Mulching Lawn Mower Cons
Some of the notable setbacks of mulching mowers are:
🌧 They’re Not Suitable For All Occasions
There are some occasions when mulching simply isn’t suitable.
For instance, if the grass is wet and you have no choice but to mow your lawn, mulching isn’t advised because the grass clippings will clump together on your lawn, suffocating the grass underneath and causing patches of your lawn to turn yellow.
Plus, if you have a weed problem in your lawn, mulching will only make the matter worse by spreading the weed grasses all over your lawn. What might have started as a minor issue in just one part of your lawn will quickly become a major weed problem that could take months to resolve.
The same goes for certain lawn diseases that could be spread by depositing the diseased grass leaves onto other parts of your lawn. Using a mulching mower is a terrible idea in this situation because you want to prevent the spread of disease as much as possible.
So, while the perks of a mulching mower might appeal to you, keep in mind that you might not be able to use the mulching function 24/7, for the sake of maintaining a green, healthy lawn.
🟩 They Won’t Produce A Neat, Tidy Lawn
If you love the look of a neat, clean lawn after mowing, you probably won’t appreciate the fact that mulching mowers deposit grass clippings rather than collecting them up.
A mulched lawn might be healthier, but the grass clippings scattered over the soil are something of an eyesore. While they should decompose within a matter of days, you might prefer not to see them even for a short period.
In this case, ask yourself whether a mulching mower is the right mower for you. Perhaps you would actually prefer the extra effort of dumping your grass clippings on your compost pile to avoid blemishing your freshly cut grass with decomposing clippings.
💰 They May Add To Upfront Cost Or Cost Extra
A lawn mower with a built-in mulching plug is typically around 10-15% more expensive than a similar mower model with no mulching plug.
In general, mulching lawn mowers are slightly more expensive than mowers that solely offer grass collection. You pay for the additional materials, parts, and functioning required for the mower to switch from mulching to grass collection, and for the extra perks of having multiple cutting options.
Some mowers don’t come with a built-in mulch plug, but have a separate mulching attachment that you can buy at an extra cost. Mulching accessories cost £30-£45 extra on average, depending on their size and complexity.
That’s not to say you can’t find a budget-friendly mulching lawn mower (our top recommended mulching mower for small budgets is the GardenTek Mulching Mower, which costs less than $100 and comes with a rear roller), but in general, you should expect to pay more for a mower with a mulching function.
📏 They’re Not Suitable For Long Grass
If you let your grass grow too long before you bring the mower out, you’ll have to abandon mulching and make use of your mower’s grass collection bag.
A mulching lawn mower should only be used to cut short-to-mid-length grass. If the grass is too long, the mower will deposit an excess of grass back onto your lawn, making a mess and potentially smothering the grass underneath.
I recommend that you avoid mulching your lawn if your grass is longer than 7cm. If you really want to mulch, stick to the one-third rule. Mow your lawn once, cutting off one-third of the original blade height, then wait a few days for the mulched grass to decompose before mulching again. Continue until the grass is at your desired height.
📆 They Require A Regular Mowing Schedule
It’s true that mulching grass saves time, but you’ll also have to bring out your new lawn mower more often than if you were collecting grass in a box or bag.
As I mentioned, mulching works best when your grass is short-to-mid-length. If you let your grass grow too long, you’ll end up with too much mulch clogging up your lawn’s surface, with an increased likelihood of clumping, possibly causing your lawn to develop yellow patches.
You’ll need to mow your lawn at least once a week with a mulching mower – something that’s easier said than done if you live in the UK and are all too familiar with our wet summers.
💦 They Shouldn’t Be Used On Wet Grass
On the subject of rain, there’s no denying that we get a lot of it here in the UK. Ideally, you shouldn’t be mowing your lawn on wet days anyway – but you especially shouldn’t mow wet grass with a mulching function.
Mulch is best made when grass is dry and can easily be dispersed across your lawn. Wet grass, on the other hand, is heavy and damp, and sticks together in clumps. These clumps block the grass underneath from sunlight, leading to the dreaded yellow patchy lawn.
If you have no choice but to mow in damp conditions, you’ll need to switch to collection to avoid crushing or killing patches of your lawn.
🔒 They’ll Limit Your Choice Of Mowers
If you love your current mower and you don’t want to invest in a new one just for the benefits of mulching, you might want to see if the manufacturer sells a separate attachment for your mower type.
Unfortunately, however, many mower types don’t come with an optional mulching attachment, and it’s not the case of one size fits all – you can’t simply use a mulch plug from another manufacturer because your mower won’t have been designed to hold this accessory.
So, if mulching your lawn sounds appealing, you’ll have to look specifically at mower types that have a built-in mulching function or those that can be purchased with optional mulching attachments.
Petrol lawn mowers are the most likely to have a mulching plug, but if you want an electric or battery-powered mulching mower, you’ll have a smaller pool of products to pick from.
🤷♂️ Do Mulching Mowers Create Thatch?
No, mulching lawn mowers don’t create thatch. A common myth is that mulching mowers increase thatch and moss, but actually, the opposite is true. If anything, regularly mowing your lawn with a mulching lawnmower will reduce your garden’s thatch and moss.
What does create thatch is simply discharging your grass cuttings without mulching them first. This will result in long grass on the lawn, which will block the growing grass beneath and causing conditions that contribute to thatch growth.
That’s why it’s important to use a mower with a dedicated mulching function if you want to avoid the side-effects of simple grass discharge.
🏁 Are Mulching Lawn Mowers Worth It?
Now you know the pros and cons of owning a mulching mower compared to collection-only mowers, you can decide whether this type of mower is a good fit for you.
I think mulching mowers are worth it for people who want to eliminate the hassle of emptying a grass box or raking clippings off the lawn after mowing. If you want to reduce your mowing time and get the job done faster, while also feeding your lawn with natural fertiliser that will support healthy grass growth, a mulching mower should meet your needs exactly.
However, if you prefer to have a neat, tidy lawn that’s free from grass cuttings after mowing, a mulching lawn mower might not be for you. Plus, I don’t recommend buying a dedicated mulching mower that doesn’t offer the option of grass collection because there may be times when mulching isn’t suitable and could be detrimental to your lawn health.
Ready to start your search for the best mulching lawn mower? In our best mulching mower guide, we’ve shared reviews of all the top mowers in this category available today.