A Step-by-Step Guide to Removing Grass from Under A Raised Garden Bed

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If you’re considering creating or buying a raised garden bed, you’ve probably debated whether or not you should be removing the grass from your designated location. If you’ve done this, congratulations, as you’ll need to implement this to enhance the effectiveness of your garden beds. But why do you need to remove grass from under a raised garden bed before it’s placed?

Before placing down your raised garden bed, you’ll need to remove the grass because it’ll soak up vital nutrients from the soil, which can be problematic for your plants in the future. Apart from stealing “food” from your plants, it also reduces the space they have to grow.

Many raised garden bed owners that don’t correctly prepare their designated location encounter one of the above issues. Either way, they have the same outcome as your plants or vegetables won’t fully develop the way you’re hoping for.

In the world of gardening, this is a common issue. Being an avid gardener myself, I wanted to help out my fellow hobbyist and create a detailed guide based on grass and raised garden beds.

Do you have to remove grass under a raised garden bed?

In short, yes, it’s highly beneficial for your plants to remove grass from underneath your raised garden bed. Grass is the same as any plant-based organism, as it needs nutrients from the soil to grow. Therefore, if you place your raised garden beds above the grass, the grass can potentially steal these nutrients to continue growing.

If the grass starts growing into your bed, this can cause heaps of issues for your plant’s development. As the grass gets larger, it needs more nutrients to flourish, making the results even more devastating. Because the grass is growing, it’ll also disrupt the potential room other plants in the bed have to develop.

As you’re able to grasp, it’s incredibly vital to remove grass from beneath your raised garden beds altogether. This is because it’ll massively interrupt the development stages of your plants, which may even cause them to die.

How to effectively remove grass for a garden bed  

If you’ve read the above, you probably want to remove your grass from the underneath of your garden bed. Hopefully, you’re implementing this before you lay your beds down. If not, you can still follow the below methods after removing your garden beds from the area.

To successfully remove grass from a designated area, you’re able to achieve this in four different ways. These are by:

  • Digging
  • Using a tiller
  • Herbicides
  • Smothering the grass in either plastic, cardboard, or newspaper

Each of the above methods is an effective way of removing grass from a specific area. Below we go into more detail about how you can execute them correctly to ensure your grass doesn’t grow back.

Digging

The first and most popular method is to remove the sod with either a spade or fork. If you have enough willpower and strength, you’ll be able to lay your garden beds down the same day as the removal. This is definitely a simple method of removing grass, but you may encounter sweat and sore muscles after this good workout.

To make this process a lot easier, you should water the area a few days before you remove the grass. When applying water, try to keep it moist but not extremely soggy, as this could make digging even harder. However, if you get the consistency right, you should experience easier digging.

You should also consider not throwing away your grass, as with this method you’re able to roll it up into small sections and re-lay it elsewhere. Grass is a valuable organic material that provides excellent benefits to our environment, so keeping your sod instead of destroying it is much more economical.

  • Pro – From digging, you don’t need to use harmful chemicals or loud power tools.
  • Con – On this list, digging is the most labor-intensive and not something everyone will particularly want to do.
  • Helpful tip – To increase your digging efficiency, you should sharpen your spade and also opt-in for spades that come equipped with soft handles.  

Tiller

If digging is too labor-intensive for you, a good option would be to either invest or hire a tiller. A tiller is a small power-operated cultivator which will do nearly all of the work for you. For most gardens, a tiller will be powerful enough to remove the grass successfully. However, if your garden is known to be dry, you may need to opt-in for a heavier duty tiller to effectively remove your grass.

A considerable benefit you’ll receive from tillering is that the grass is killed and then relayed into the soil, which provides the ground with some excellent nutrients. Another remarkable benefit is that after you’ve tilled and leveled out the area, you’re able to lay your garden bed directly on top of the tilled area without any issues.

  • Pro – Recycles organic matter (grass), and it’s much easier than many other methods mentioned on the list.  
  • Con – If your ground is hard, rocky, wet, or has a lot of clay, a tiller can sometimes struggle.
  • Helpful tip – Large tillers can be remarkably hard to maneuver. Try not to till the border or edges. Instead, do this manually with a spade, fork, or edger.

Herbicides

Another standard method is to use herbicides. However, this can be frowned upon in the gardening world due to the harmful chemicals that can be found within them. Although these will kill the grass, they’ll also damage the soil and significantly impact the environment around it.

If you’re choosing the herbicide method, you should select an appropriate product. Some herbicides are created to kill broad-leaved plants rather than just grass. Meaning that it can potentially kill many other plants around the area where you spray this chemical. If you can, choose a herbicide that is primarily for grass as this will dramatically decrease the negative effects on plants around your sprayed areas.  

  • Pro – Extremely easy to use, making it an ideal solution for all gardeners.
  • Con – Can contaminate other plants in the surrounding area, causing them to die with your grass.
  • Helpful tip – Try to opt-in for a grass-only herbicide and read the label’s directions for the best use and disposal.

Smothering

This last method is straightforward to implement and also good for the environment. The only downside is that it’ll take several months to kill the grass successfully. To effectively smother your grass, you’ll want to layer your grass with plastic, newspaper, or cardboard. This will then eliminate all the healthy nutrients that the grass receives from the sun and rain. Because of this, it’ll slowly die over time. Here’s how you can implement each method depending on the materials you use.

Plastic – If you’re going to use plastic to smother your grass, you’ll want to cover a designated area with a thin layer of plastic and anchor it to the ground. Using something like tent pegs is a perfect solution for this. Unlike newspaper and cardboard, plastic isn’t biodegradable, so you cannot layer it with soil until you remove the plastic.

Cardboard or newspaper – To use cardboard or newspaper to smother your grass, you’ll want to lay it down in a specific area of your choice. Because it’s biodegradable, you’re able to cover this with materials like leaf mold, compost, or any organic matter. Using cardboard or newspaper is less effective than plastic as it doesn’t get as hot underneath, but it’s certainly more organic.

  • Pro – It’s exceptionally effortless and can be relatively good for the environment if you don’t use plastic.
  • Con – Using this method will slowly kill grass and will take several months before it takes full effect.
  • Helpful tip – For the most effective results, lay your smother during the summer, and by next spring, your grass should be dead.

How to remove grass from a pre-existing garden bed

If you’ve already installed your garden beds over grass and cannot remove them. It would help if you considered the following methods for removing grass from a pre-existing garden bed. Below we go into detail about two solutions, using an herbicide and also some organic processes.

Herbicide

The word herbicide does make most gardeners cringe, and that’s why I’ve suggested some organic methods below. However, using an herbicide is probably one of the more effective ways to eliminate grass from your pre-existing flower beds. If you can, purchase an herbicide that is mainly used for grass, as others may negatively affect your plants.

NOTE – Always read the bottle before the application in case it damages your other plants located inside the bed.  

Organic methods

Something that brings joy to many avid gardeners is the word organic. At the end of the day, we love gardening so much because we adore our environment, and using harsh chemicals isn’t something we want to opt-in for. Below are some organic methods you can try to kill grass.

  • Vinegar – If you diluted vinegar and apply it onto grass, it will eventually kill it. However, it will take several coats before it dies.
  • Boiling water – The oldest trick in the book is boiling water, simply pour boiling water over the grass to kill it.
  • Flame – Using flames can also organically kill grass that is growing inside of your raised beds.
  • Corn gluten – For many gardeners, this is a go-to option for removing grass or any type of weeds. Apply the corn gluten to a designated area and let it do the rest.

What should be under a raised garden bed?

Now you’ve successfully killed the grass on your soon-to-be garden bed location. What should be underneath the bed? Well, there are three base materials you’re able to choose from. This can be plain soil, wood, or stone. Each offers the same benefits, but using wood or stone provides you with a more stable surface and better protection from anything trying to grow below your garden beds.

Soil

As we’ve mentioned above, soil can be used as a base material for your garden beds. However, you’ll need to make sure you’ve successfully destroyed the grass before laying your bed above. Failing to do so can create havoc for your plants that are located inside of your garden bed. This is because the grass will steal vital nutrients that are flowing through the soil.

Wood

People tend to use wood so that the soil underneath doesn’t become too compact. But the only massive downfall from this is that wood is very susceptible to rot. If you’re going to choose wood as a base for your garden bed, make sure you purchase treated wood to reduce the chances of rotting.

Suitable wood species that don’t rot quickly would be something like cedar or redwood. These are well-known to last upwards of 10 to 20 years before having to be replaced. You should also consider a wood composite product, as these are made to be highly durable.

Stone

Another base material that is commonly found underneath garden beds is stone. Stone is excellent, but you have to be careful with the type of stones you choose. It would help if you used small shingle-like rocks, as these work superbly with drainage. If you use big stone slabs, then this will restrict the drainage, and doing this will ruin your plants if you have any heavy rain.

As you can see from the above, there are a few base materials you’re able to opt-in for to provide a stable surface for your garden bed.

Can you put a raised garden bed over grass?

In theory, you can lay a raised garden bed anywhere you like. However, it doesn’t mean you should. From laying your bed over grass, the grass can grow into your bed and start stealing crucial nutrients that are valuable for growth. If this occurs, your plants in the bed will grow poorly or even die in some cases.

To save yourself the hassle, I would remove the grass from where you’d like to place the bed. This way, you won’t encounter these issues in the future. See above to find out how you’re able to remove grass effectively.

Conclusion

After reading this article, you should understand that preparing the location of your beds is vital. Failing to do so may result in growing difficulties for the plants you place within them.

Either of the methods above is an excellent way to effectively remove grass from a large or small area. Nonetheless, all gardeners need to implement some type of shielding from grass growing inside of their raised beds.