To mulch or not to mulch, that is the question – but do all lawn mowers have a mulching function or not?
Not all lawn mowers can mulch. Mulching mowers have curved blades and a domed cutting deck to cut, suspend and recut grass into tiny pieces that are deposited on the lawn, whereas conventional mowers have flat blades that cut just once. You can use a special kit to convert your mower to mulch.
Let’s look into the subject of mulching lawnmowers in greater detail, so you can work out if you need a mulching mower for your lawn – or not…
What’s The Difference Between a Mulching Mower and a Regular Mower?
The difference between a regular lawn mower and a mulching mower is two-fold: the shape of the body of the mower and the blade.
Regular lawn mowers use a fairly flat blade to cut grass. Once it’s cut, the blade throws the grass pieces out of the mower and onto the lawn or into a bag.
Regular lawn mowers are the choice of lawn professionals because they can use fast-moving mowers and get the job done as quickly as possible.
A mulching lawn mower cuts the grass, too, but instead of the clippings being thrown out immediately, the pieces of grass are re-circulated around a curved blade, inside the body of the mower, several times.
A mulching lawn mower has a wide, high-domed deck design that helps to suck up the grass cuttings. Some mulching mowers even have baffles built into the deck.
Not only does a mulching lawn mower have a different shape, it also has a different blade. A mulching blade is curvy, and it has a larger cutting surface. The blade’s shape helps to move the cuttings up into the domed deck, then when the grass falls back down, the additional cutting surfaces chop them up.
The grass gets suspended, chopped, suspended, chopped, until finally the pieces are so small, they fall out onto the lawn. When the pieces finally fall, they are very small – an inch or less.
This small size is perfect for mulch. Grass is mostly water. During the summer, the small pieces of grass will decompose back into the lawn in a few days.
Do I Need a Mulching Lawn Mower? (Are They Any Good?)
These days, we are all trying to do small things every day to help our planet. Mulching your grass clippings is on that list. Mulching grass clippings is a thing – it’s called grasscycling.
Grasscycling is good for your lawn and it’s good for reducing landfill volume. In many states in the US, yard wastes like grass clippings and leaves are banned from landfills.
Mulching lawnmowers work great. Sure, you might have to walk slower behind a mulching mower. But if you have a good spread of healthy lawn, a mulching lawn mower can help you cut down on the time you spend taking care of it.
With a mulching mower, there’s no raking. No stopping ten times to bag clippings. No giant piles of grass that you have to dispose of. No walking back and forth fertilizing twice a year, or more. Experts say that by not bagging, you can save up to 30% of your lawn care time.
You’ll have more time enjoying your family, grill-mastering and enjoying those Tiki drinks with the little umbrellas.
Can I Turn My Mower Into a Mulching Mower? (Can I Change The Blades?)
Several models of ordinary mowers can be turned into mulching ones with just a blade change or a conversion kit. They won’t have the domed deck design of a mulching mower, but they will mulch just fine.
First, do some research on whether your mower can operate safely without a bag. Not all can. Check out your owner’s manual or call your equipment dealer.
Many manufacturers offer a conversion kit that allows you to switch your standard (aka high lift or 2-in-1) blade for a mulching (aka 3-in-1) blade. Be sure to do some research for your particular mower manufacturer, because not all blades are universal.
It always helps to keep mower blades sharp, but it is essential with mulching blades. Experts say the rule of thumb is to sharpen blades at least yearly or every 25 hours of use.
Is it Better To Bag or Mulch Your Grass?
Environmentalists and lawn experts all say: mulch your grass if you can. Yes, there will be times when you can’t, but try to make mulching – grasscycling – your new standard practice.
The number one reason to grasscycle is that it returns nutrients back into your lawn. It helps reduce the need for chemical fertilizers.
Grasscycling can also help cut down water usage – because the cuttings are 80% water. It can help cut back on the weeds in your lawn.
No bagging helps reduce plastic volumes in landfills and all the associated microplastic issues. Here’s a great reference on the benefits of lawn mulching.
However, there are times when mulching may not work.
If you live in a wet climate, you may need to bag your clippings if you don’t get a dry spell and you just have to mow. If your lawn is too wet, the cuttings may bunch up and end up in piles on your lawn, instead of being spread out. Bunched, long clippings left on your lawn can smother it.
It’s better to bag your clippings when your lawn is suffering from a disease like leaf spot, rust or dollar spot. Get those diseased clippings out of there by bagging. Then, tackle the diseased areas.
Expert opinion is divided about mulching fall leaves. Some say that the volume of fall leaves is just too much for mulching lawn mowers to do a good job. The result is bunches of ripped up leaves on your lawn in piles, which take a lot of time to decompose and might suffocate your lawn.
Other experts say that mulching fall leaves makes for a great nutrient add to your lawn. The answer may depend on the type and volume of leaves – get the opinion of your local agriculture extension agent.
If you do bag your grass clippings, please consider adding them to flower beds and compost bins – don’t leave them stacked up in a pile of bags for the trash truck.
The good news is, for many new mowers, you can have it all. Mulching and bagging.
What Are The Benefits of Mulching?
Grasscycling helps build a healthy lawn. Mulch adds organic matter to poor soils. If your soil is sandy or clayey, mulch can improve the texture.
Grass clippings contain phosphorus, nitrogen and potassium – the same chemicals in fertilizers. Experts say that clippings can reduce or replace the need to fertilize. But if you have fertilized, be sure to mulch and not bag up the clippings (with the expensive fertilizer).
What Are The Disadvantages of Mulching?
Some experts say that if you have a struggling lawn – lots of bare patches – then mulching may actually hurt instead of help. Mulch can hide the problem areas. Experts recommend bagging the cuttings and concentrating on improving the lawn health.
Here’s an article on some disadvantages to mulching.
If your lawn has patches that are diseased, then you should bag your clippings, or you could spread the disease with the mulching process.
If you tend to leave your mowing to the very last minute and the grass is kinda long, then bagging might be better than mulching. Overgrown grass is difficult for a mulching mower to process.
The blade will slow down and rip – not cut – the long grass. Big wads of long grass can smother your lawn.
Mulching lawnmowers use a lot of horsepower recirculating the clippings. When the lawn is wet, a mulching lawn mower may not do a good job cutting and may be slow. In wet climates or wet seasons, you may need to bag your clippings.
Some experts recommend bagging if you are just starting your lawn from seed. New seedlings may not be strong enough to withstand mulch – even tiny mulch – on top of them.
It certainly seems the case that if you want to promote good lawn health – and help save the planet – then a mulching lawnmower could be the right way to go.
‘Grasscycling’ may be a new word for an old way of doing things (I’ve been cutting the grass with a mulching mower since I was a teenager), but it now seems that climate science backs up this way of mowing.
So if you’re in the market for a new lawnmower, perhaps a mulching model is a good choice – and if you have a non-mulching mower, then maybe a blade conversion kit to make it a mulcher will be a good investment both for your lawn and the environment. 🙂