Gardening Gardening Basics Garden Tools

What Are Mulching Mowers, and Do They Really Mulch Properly?

Fertilize the lawn while simultaneously saving yourself time

By
David Beaulieu
David Beaulieu
David Beaulieu

David Beaulieu is a landscaping expert and plant photographer, with 20 years of experience.

Learn more about The Spruce's Editorial Process
Updated on 12/01/23

Purchasing a new lawn mower can be a challenging decision with the breadth of options on the market. If you're looking to purchase an effective mower without gas or electric, consider a mulching lawn mower.

A mulching mower is a popular option for homeowners, as this mower offers multiple ways to get rid of grass once it's cut. The mulching mower chops grass blades multiple times and deposits the grass back onto the lawn, creating a built-in "mulch" that refeeds and shades the soil.

Budget, lawn size, ease of use, safety, and a number of other factors must inform your decision when deciding to buy a mulching lawn mower. Read on to learn all about mulching mowers: what they are, how they work, how they differ from regular mowers, and what types are available.

What Is a Mulching Lawn Mower?

A mulching mower is a type of lawn mower designed to minimize the size of the grass clippings left behind. In fact, the grass clippings deposited by mulching lawnmowers are torn into such tiny particles that you will hardly notice them.

Once these particles come into contact with the soil, they quickly begin to decompose. This decomposition is beneficial to the soil and also helps you avoid the problems associated with the coarser clumps of grass clippings that can be left behind on the lawn by non-mulching mowers.

Do mulching mowers make mulch?

"Mulching" mower is a bit of a misnomer, as they do not make mulch, but rather leave grass clippings behind as more of a compost. This source of organic matter breaks down and supplies your grass with nutrients. By contrast, if you want to mulch around a shrub to suppress weeds, you would typically apply a bark mulch.

Cutting and bagging grass and leaves in the fall
Ozgur Coskun / Getty Images

How Does a Mulching Mower Work?

The reason why a mulching mower is able to cut the grass into fine particles is that its cutting blade has more of a curved shape than does the blade on other types of lawnmowers.

Due to this blade shape, a mulching mower is able to retain the grass clippings longer within the mower deck as the blade spins.

The longer they are retained, the more cuts are made, and the finer the resulting particles become before falling to the ground.

Grass clippings clumped together on grass lawn in front of lawn mower

The Spruce / Steven Merkel

Mulching Mower vs. Regular Lawn Mower

The alternative to a mulching mower is a "regular" lawn mower that comes with a bag attachment to collect grass clippings. If the lawn mower does not have a bag attachment to collect the grass clippings, then homeowners will typically rake up the clippings to get them off the lawn.

You can add them to your compost bin, where they serve as an excellent green material for your compost.

Mulching leaves with lawn mower
A mulching mower can make light work of a thin layer of dry leaves. Kathleen Groll Connolly

Collecting the clippings rather than leaving them on the lawn has its pros. Your grass clippings could become bulky if you leave too many in one pile, and the result will be an unwanted build-up of thatch in your lawn.

One selling point for mulching mowers is that using this type of mower gives you a free, organic way to keep your grass fertilized. It allows you to avoid having to buy and apply chemical fertilizers to feed your lawn.

A second selling point of mulching mowers is their ease of use. With a mulching mower, you do not waste time and energy either raking up grass clippings or emptying a bag attachment.

Types of Mulching Mowers

You can choose a mulching mower based on a number of different factors, including cost, power source, and lawn size.

Power Source Options:

  • Corded electric
  • Cordless (with a battery)
  • Gas

Which you choose will depend on your wants and needs. Corded mowers are less expensive than battery-powered ones, but it might be worth upgrading to cordless since dragging a cord around can be inconvenient.

Gas mowers offer more power and capabilities than electric ones. For example, if you tend to forget to mow, thereby allowing the grass to grow too high, a gas-powered mower will generally handle the challenge better than an electric model.

Why Lawn Size Matters

The larger the lawn, the harder you have to work to mow it (and the longer it will take). But you can reduce your workload by selecting the right type of mulching mower.

One feature to look for is deck size. The larger the deck, the greater the swath you can cut on each pass as you mow. This, in turn, reduces the number of passes you must make to complete the job.

Another way to reduce the time and energy needed to mow a lawn is to choose a unit that moves under its own power rather than requiring you to supply the power by pushing it. There are two types of walk-behind mowers:

  • Push mowers: As the name suggests, they move only when you push them.
  • Self-propelled mowers: Instead of having to push a self-propelled mower, you guide it.
FAQ
  • Do mulching mowers work well?

    Using a mulching mower will simplify your lawn-mowing experience because you won't need to rake grass clippings or empty them out of a bag attachment.

  • What's the difference between mulching mowers and regular mowers?

    Regular mowers cut the grass and propel clippings through an exit channel. Mulching mowers cut the grass more finely and reapply the clippings to the lawn, where they act as fertilizer. 

  • Are mulching mowers good for the environment?

    Mulching mowers are good for the environment because they lessen the need for artificial fertilizers, eliminate the plastic packaging for those fertilizers, and release micronutrients into the soil that artificial fertilizers may lack.