Can a Lawn Mower Spread Weeds?


No matter what you do, weeds are here to stay.

Although some may argue there is a good side to weeds, I say that the majority of us don’t really like having a backyard full of weeds.

So if you want to maintain a healthy-looking lawn, you need to know how to keep the number of weeds down to a minimum. And the first step is to find out what spreads them.

Is it just nature doing its work, or is there something more to it? Well, the answer is both. Here’s why.

Can a lawn mower spread weeds? Yes, lawn mowers can spread weeds. Weeds and their seeds can get stuck under the deck of the lawn mower. Their seeds then can easily fall into other areas of the lawn, and thus spread even faster.

With that being said, I found out that there is a lot more to weeds than it meets the eye.

They may be stubborn little plants, but by better understanding how they grow and spread, we can reduce the chances of having to deal with them in the future to a minimum. Read on as I get into more detail about all that.

Why Are Weeds Bad for My Lawn?

First, let us start with the fact that in nature, weeds always win.

That will be okay, but not many of us like the idea of having a messy back and front yards full with weeds and all kinds of stuff.

The problem is that weeds and grass compete for the same nutrients.

Weeds usually have stronger and deeper roots and can reach and absorb the nutrients from the soil and fertilizers much quicker compared to the normal grass.

As you might imagine, this puts grass at a severe disadvantage.

As a result, weeds will eventually starve the grass from water, nutrients, and even air.

This is not only going to damage and kill your grass, but it will also make it so weak that even disease, insects, fungus, and more can further exacerbate the situation.

And if that was not enough, weeds also compete for space.

They tend to produce a lot of seeds for the sole purpose of spreading out. Some types of weeds can be very aggressive. In other words, things can go from bad to worse real fast.

How Do Weeds Spread

Weeds, just like any other type of plant, go through a life cycle. As they grow up and mature, they will produce seeds.

These seeds then fall off into the ground. And once the seeds are in the ground, they will start growing and repeating the same cycle all over again.

Many people think that weeds just grow back even if you mow them. But it may not be the same plant, but rather a seed that fell from it.

The Elements Can Spread Weeds

The main way weeds spread is by air and wind. A single windy day can result in the spreading of the weeds’ seeds across large areas. So if your neighbor has them, the chances are sooner or later the weeds will reach your lawn too.

Water and rain can spread weeds as some have adapted to float on the water to reach new areas.

The bad thing here is that, well, you cannot really do much to prevent the seeds from spreading by air.

Machines Can Spread Weeds

When you mow, some of the grass clippings and dirt will stick underneath the mower’s deck. If you come across weeds and mow them, the chances are some of their clippings and seeds will also stick to the undercarriage of your mower.

As you mow, these cuttings can drop and spread the seeds of the weeds.

Also, if the company you have hired doesn’t clean their mowers, they can easily introduce weeds from other lawns to your own.

Anyone who’s owned a lawn care and maintenance business will tell you that if they mow a lawn with lots of weeds in the morning by the end of the day, every other lawn will be contaminated with weeds (provided they don’t clean the mower properly).

And last but not least, another way weeds can spread is by using cheap and low-quality grass seeds.

People and Animals Can Spread Weeds

The seeds of weeds can potentially stick to any surface.

Weeds can get stuck to your boots or clothes or on your pet’s fur.

Let’s not forget that many seeds have adapted in such a way as to pass through the digestive system unharmed. So even a bird can introduce weeds to your lawn.

Unfortunately, there is not much we can do in this case, either.

What we can do is take some preventative measures.

How to Prevent Your Lawn Mower from Spreading Weeds

In many cases, we may not be able to stop the weeds from spreading. However, when it comes to our lawn mower, things are a bit different. Here we have a certain amount of control.

Here are a few tips that you need to know if you want to reduce the number of weeds in your lawn.

Clean Your Lawn Mower

First and foremost, always clean your lawn mower after mowing a yard that has been contaminated with weeds.

If things are getting out of control, I would even suggest cutting your grass in two goes. First, go over the parts of the lawn that do not have weeds. And then over the patches with the weeds. When you finish, clean the mower.

Make sure to follow the cleaning procedures, which have been outlined in your user’s manual that came with the mower.

Mow Your Grass the Right Height

Another aspect that you need to pay extra attention to is the height you are cutting your grass at.

Do not cut the grass too short. This can be bad for two main reasons:

  • It can weaken the grass, making it easier for the weeds to overtake it; and
  • Short grass can open bare spots and areas where weeds can be able to reach the soil, germinate, and grow.

Mowing itself can also be an effective way to kill off weeds if done at the right time before a frost or before a period of dry weather.

What to Do If Your Lawn Mower Has Already Spread Weeds

Now that you know even your lawn mower may introduce weeds to your green oasis, you know how important the proper cleaning and maintenance of the mower are.

But we may be too late. You may already have weeds growing in your backyard. This can make things a bit trickier but in no way impossible to deal with.

Bag the Clippings

Whenever you are mowing your grass, make sure to always bag the grass clippings.

You want to catch and hold as much of the grass as possible. That way, you will prevent your lawn mower from spreading the weeds, or at least prevent most of it.

Be Mindful of the Mulch

There is a lot of data showing the benefits of mulch when it comes to weed control. And you can easily use your grass clippings and leaves as mulch.

Don’t use mulch from a lawn that may have weeds growing in it. This will just result in your lawn mower spreading the weeds even more.

For example, if you are going to pick up leaves with your lawn mower and use them as mulch, make sure you are not cutting any weeds that may be below the leaves.

Use Weed Killers

If it is too late, one of the best ways to reduce the impact of weeds is to use a weed killer. With younger plants, even one application can be enough. However, with more mature weeds, several applications may be required.

Weed killers have to be used with extreme care as they are very strong and can also damage your lawn if used incorrectly.

Manually Pull out Weeds

Probably the least pleasant method to deal with weeds, but nonetheless a very effective one.

Of course, this is viable for very small lawns and yards where the number of weeds is too small to justify using a weed killer. It’s an easy and simple method that does not cost you anything.

Just pull out the weeds before you proceed with mowing your grass. That way, you can prevent your mower from spreading the weeds.

Additional reading and resources:

http://ceventura.ucanr.edu – An Alternative Weed Control – Mulching
https://www.oasisturf.com – 9 Reasons You May Not Get Rid of Weeds in Your Lawn and What to Do

Peter Toth

Hi! I'm Peter, the owner of BackyardGadget. Working around the house has always been a big part of my life. I've created this site to share my experience, and to help people choose the right tools for the job. Thank you for stopping by!

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