Can You Put Mulch Over Grass

Can You Put Mulch Over Grass? (Do’s and Don’ts)

Converting your grass lawn into a vegetable or flower bed is one way of adding new life to your yard. You need to get rid of the grass and enrich your soil so that your new plants thrive. You’re probably wondering, “can you put mulch over grass?” killing two birds with one stone, right? 

Yes, you can put mulch over grass. It’s a way of suppressing the grass by cutting off its sunlight and air supply, which is necessary for its growth. Over time, the grass stops growing, leaving you a new planting area. The mulch, dead grass, and barrier materials later decompose, enriching the soil. 

This article discusses the guidelines for laying mulch over grass in depth. Read on to find out how to prevent grass from growing through the mulch. 

Alsoc CHeck: Can Rubber Mulch BE USed Around Plants?

Can You Put Mulch Over Grass?

Yes, it’s okay to lay mulch over grass if you need to clear your grassy lawn leaving you a new planting site. Pulling out the grass might not be the most effective solution since it often grows right back. Using mulch is a safe and permanent method of suppressing grass. 

Cover the grass with a layer of mulch to suppress the grass and stop it from growing. The mulch helps in cutting off the grass air and sunlight supply. As a result, this provides a barrier to its development.

The ideal way to apply mulch is by spreading it on top of the grass to get nutrients found in it for lawn and gardening purposes.  

However, you can leave the mulch there permanently. The dead grass and the mulch eventually decompose, adding more nutrients to your soil. 

Why Should You Put Mulch Over Grass?

If you’re planning to replace your lawn with a flower or vegetable bed, ensure you do it properly. Incompletely killed turf can re-sprout among your new plants, ruining your new landscape look. 

The main reason you should put mulch over grass is to kill it. One of the methods of killing grass by laying mulch over it is sheet mulching which kills grass by starving it of light. Sprouting grass also reduces because it cannot anchor its roots deep into the soil.

Putting mulch over the grass to get rid of it works well for all types, including perennial and annual weeds and Bermuda grass. It helps to prevent aggressive re-sprouting of the grass. 

If left in place, the dead plants, the mulch, and the barrier materials break down into compost, improving the soil’s fertility. It helps your new plants thrive, ensuring the long-term success of lawn replacement. 

Sheet mulching has gained popularity because it’s an environmentally-friendly way to kill the grass. It’s also cost-effective as the materials used are affordable. Additionally, you can do it at any time of the year. 

Over time, once the mulch-covered grass stops growing, you’ll be left with a new area for sowing new plants. The new crops grow free of competition for nutrients from pesky grass, transforming your lawn into a beautiful vegetable or flower bed.  

Putting mulch over grass enables you to convert some lawn areas into vegetable or flower beds. 

How To Lay Down Mulch Over Grass

Before you begin, ensure you have all your materials gathered for a smooth experience. You need the following materials:

  • Lawnmower
  • Newspapers and cardboards. Glossy colored pages are unsuitable because they may contain metallic traces, which are harmful to the soil.
  • Water
  • Compost
  • Mulch such as wood chips

With everything ready, here’s how to lay down mulch over grass:

  • Cut down the grass: It would be best to cut down the grass since you’ll be covering the area with newspapers, and it lays better over short grass. Mow your yard using the lowest setting on your lawnmower. However, if your grass is less than 3″ long, you may skip this step. 
  • Get rid of any perennial weeds such as oxalis and dandelions: Perennial weeds are undesirable plants that re-sprout yearly from the same root and can regrow after the mulch has broken down.
  • Water the soil for it to hold the newspaper more firmly: To avoid a runoff, water it in intervals. Apply a small amount of water and let the soil soak it in before repeating the process as necessary. 
  • Place sheets of cardboard or newspapers over the site on a windless day: The newspapers should be 10-12 sheets to get a thick layer enough to kill the grass. It’s necessary to overlap the edges of your barrier material by 4″ to cover the area thoroughly. 
  • Wet the cardboard or newspaper: While at it, weigh down the paper to hold it in place as you lay the mulch. Remember to check for any spots where barrier material may have shifted. Take care when you’re walking on the wet newspapers as they tear easily. 
  • Spread a layer of compost: Spread about 3″ thick of compost on top of the newspaper or cardboard to help in decomposition. 
  • Apply and spread the mulch over the cardboard or newspaper: It needs to be at least 4-6 inches to block the sunlight. Light is food for plants, and therefore the grass starves to death in the darkness. Be careful when spreading the mulch not to tear or shift the barrier material. The mulch, which in this case, could be wood chips, helps to hold the compost in place. Furthermore, it eventually decomposes, adding more nutrients to the soil. 
  • Water the site: Watering the site helps compact the mulch. 
  • It’s advisable to wait for about 3 months before planting in the yard. It provides ample time for the mulch to kill the grass and break down the barrier materials. You need only wet the mulch during this period if the high winds threaten to blow it away. 

How To Prevent Grass From Growing Through The Mulch

Even though putting mulch over grass discourages it from growing, some are stubborn and may still sprout. One way of preventing grass from growing through mulch is by using landscaping fabric. 

The fabric is placed over the soil and covered with mulch. It acts as an additional barrier against the sun’s rays, preventing grass from growing. 

Reseeding grass above the fabric is blocked from penetrating its roots deep into the soil, so you can easily handpick them. Sitting under a layer of mulch helps to extend the fabric’s lifespan. Landscaping fabric is readily available in most plant nurseries and home improvement stores. 

Vinegar is another natural and inexpensive way of killing encroaching grass. Mix a small amount of vinegar and liquid dish soap for a thicker consistency. The soap washes off any waxy coatings on the grass for the vinegar to be more potent. When you spray it on emerging grass, the solution sticks to it and kills it off. 

You can also use salt as a spot treatment for natural grass killer. The salt dehydrates the grass, which then withers off.

Additionally, you should ensure that the edges around your lawn or flowerbed are correctly defined. A deep and well-defined edge prevents grassroots from growing under the mulch. 

Take precautions before using a chemical to kill your grass. The substances are ecologically unfriendly and can inhibit the growth of new plants in the future.

Should You Use Organic Or Inorganic Mulch Over Your Grass?

If you’re mainly interested in the health and fertility of your garden, it’s best to use organic options. They’re nutritious to the soil and improve its water retention capacity. It’s a great choice if you plan to give your lawn replacement a healthy jumpstart. 

On the other hand, inorganic mulch is ideal for boosting your garden’s aesthetics. There’s a range of colors and styles to give your garden the sleek, stylish look you want. Also, it’ll completely smother and kill your grass. Inorganic mulch lasts longer than organic mulch and prevents grass regrowth for a longer time. 


How Does Mulch Kill Grass Underneath?

Putting mulch over turf kills the grass underneath. Grass needs soil nutrients and sunlight to survive. The mulch creates a barrier that prevents the grass from accessing sunlight; they inevitably perish. A thick layer of mulch prevents the grass from reseeding. Even those that don’t die off are too feeble to push through the mulch.

What Type Of Mulch Can You Put On Grass?

For organic mulch, some alternatives are pine needles, sawdust, shredded bark, wood chips, sliced leaves, compost, and grass clippings. However, inorganic mulch materials include black plastic, geotextiles, stones, and gravel.


It’s safe to say that yes, you can put mulch over grass during your lawn replacement project. You may do it as a DIY project or ask for the professional help from experts if the work is too labor-intensive for you to handle. 

Sheet mulching is one of the ideal and easy ways of laying mulch over grass. It helps stifle the grass growth and discourages new grass from emerging. 

It’s advisable to take time to suppress and kill the grass completely. Additionally, waiting until the weather conditions are favorable for new crops ensures the long-term success of replacing your lawn. 

Related Posts:
Can You Mulch Pine Needles? (Are They Good Mulch?)
Best Mulch For Dog Poop Area
How Many Wheelbarrows In A Yard Of Mulch?
What Is The Best Black Mulch? [What To Consider In 2024 ]
All About Mulching + [The Ultimate Guide]

Leave a Comment

Your email address will not be published. Required fields are marked *