Do Trampolines Kill Grass? Why the Lawn Dies Under a Trampoline & How to Make it Grow

By Brian Mounts | Jun 03, 2020
do trampolines kill grass

You probably either already own a trampoline (or your kids have been begging you to get one) so it’s time to think of the lawn and how this big investment effects the grass that will likely go underneath it.

The effect a trampoline can have on your grass is usually pretty significant. It may be a cause of concern for some home owners who prefer keeping a well manicured lawn. People like this frequently ask me and other lawn care professionals whether or not putting a trampoline out in the lawn will kill the grass… and if it will kill off a big spot in the lawn, how can it be stopped.

Most of the time a trampoline placed in the lawn will kill the grass over time unless precautions are made in advance. The jumping mat filters out direct sunlight and blocks water from getting to the grass underneath making it very hard for the grass to stay alive, especially if the trampoline is very big.

The thing is though that there are a number of things you can do to prolong the life of your grass and to help it to thrive, even under the less than ideal circumstance.

Let’s jump into this topic a little more and I’ll explain to you why exactly some grasses die off when you place a trampoline on them and why others don’t.

If you want to skip ahead to see how to keep the grass alive under a trampoline then click this link.

Basic Pros and Cons Of Owning a Trampoline

Like most things in life, there are pros and cons to any and all decisions you make – this is definitely true when it comes to to decision to buy a trampoline.

The benefits of owning a trampoline is that they offer a great way to enjoy the outdoors (as well as a way to get exercise) for the whole family from Spring all the way through Autumn.

A main drawbacks of owning a trampoline however is that they become a long-term extended part of your yard much like a tree or shrub does.

Thanks to the large size of a trampoline it will affect the way you take care of and maintain your lawn and landscape.

These major pieces of equipment can be tied together into the landscape nicely when you have a lot of money to spend but the fact of the matter is that most American’s simply don’t want to completely overhaul their yards to install a trampoline. They just want to run down to Big Lots or Walmart and pick up the cheapest option available that looks big enough for their needs.

If you want to try out a basic trampoline for a year or two and not kill off the grass in the event you want to get rid of it in the not too distant future then there are steps to take.

First I’ll tackle the most glaring questions as best as I can.

Do Trampolines Kill Grass?

In most cases trampolines will not kill grass unless the trampoline causes the ground under it to get no moisture or sunlight.

Many trampoline mats these days will only filter the sun’s rays allowing some to get through to the grass underneath and when they are placed over a sprinkler head the grass under the mat will easily get enough light and moisture to thrive, especially if you are growing shade tolerant grass types like Fescues in the north or St. Augustine grasses in the South.

However, if you were to ask ten trampoline owners whether or not their trampoline killed their grass then you will get a mix of both “yes” and “no” answers. This is most likely due to their own particular circumstances or maintenance practices.

Maybe a southerner had Bermuda grass which requires more sun and their grass slowly died off or another trampoline owner had their sprinkler system setup to sprinkle on top of their trampoline instead of below it, etc.

There are too many variables at play for there to be a definite answer.

It all depends on your geographic location, the type of grass you have, what kind of soil, is the sun shaded as it hits the trampoline frame and/or mat, how the mat is made, the angle the sun hits your yard, and so on.

In some cases the trampoline may even make your grass grow better. For instance a transition zone location with a cold season grass type may like the diffused light and lower temps provided by a trampoline placed over a sprinkler.

Conversely a sun-loving grass type may find the shade to be too much even if it gets enough water.

Another consideration is the mat itself. Some mats will diffuse and shade the grass below helping to keep things cooler whereas other types of mats may actually radiate heat down baking the ground and grass. Couple this with low light and poor watering and no doubt the grass will die.

Just because your neighbor complains about the grass dying in their yard thanks to their trampoline setup doesn’t mean it’s going to be the same result for you. In fact, there are many ways around this so you don’t end up getting an undesired outcome if you can help it.

Why Does the Grass Die Under a Trampoline?

Understanding why a trampoline may cause the grass underneath it to die will be useful in determining how to prevent it. Because the trampoline is placed directly over the grass, it can’t help but have an effect on how it grows.

The most common result of putting a trampoline in the yard is that the grass will die. Some people see the oposite happen but usually without taking precautions the grass will die.

This happens because trampoline mats typically prevent enough sunlight and moisture from getting to the grass underneath. In turn, the grass becomes dry and lacks nutrients, causing it to die.

This effect is lessened for trampolines that are smaller in size and this may ultimately affect your purchasing decisions.

Sunlight

In order to grow normally and maintain a lush, green appearance, grass needs regular access to sunlight. The sunlight makes grass able to produce well-needed chlorophyll, the important substance that keeps plants green & lively.

Overseeding under the trampoline regularly in the Fall with shade-tolerant grass types can help your grass stay thick year-after-year.

For most people in the US it can be helpful to overseed (under the trampoline) with one of two grass types. If you live in colder region then fescue will be both cold and shade tolerant and best capable of staying alive under a trampoline.

For warmer regions in the south a Zoysia will be both shade and heat tolerant and best suited for under-trampoline conditions.

Here is a Zoysia seed on Amazon that should be a good option for hotter areas of the country and here is a tall fescue mix on Amazon that will work for colder climates in dense shade.

Weight & Size

The weight of a trampoline itself can cause the grass to become damaged and die. This is especially true with large, heavy trampolines that can sink into the ground over time.

If your trampoline is bigger is will block more light from the ground but it will also be heavier and more likely to sink into the ground. This can cause the trampoline to be lower than intended which can cause even more light to be blocked and can even cause low spots in the ground which can lead to regular overwatering.

Too Much Water in Low Lying Areas

An extremely important thing to consider is if your yard has proper drainage. Without proper drainage, you may end up with a pool of water under your trampoline.

This is bad not just for the grass but because the legs of your trampoline sink it usually resulting in an uneven jumping surface that may have been perfectly flat when you put the trampoline in the spot originally.

Can Grass Grow Faster Under a Trampoline?

In some cases, trampoline owners find that the grass underneath grows taller, faster, and lusher. This can be because the geographic location is hot and the trampoline is placed in direct sunlight.

While this might sound relieving if you happen to live in a hot climate, it’s important to consider that this area of your lawn will require more maintenance so the area doesn’t become overgrown.

Obviously mowing the lawn under a trampoline can be tricky so we have a guide to keeping it tidy here.

Can You Grow New Grass Under a Trampoline?

If you’ve already experienced grass dying underneath your trampoline, then you’ll be pleased that it is possible to bring the grass in this area back to life. It’s an easy process that can fix any type of damage your trampoline may have caused.

The fix is often as simple as re-planting grass seed – usally a different type of grass that is better suited to the moisture, heat, and light conditions of your under tramopline micro-climate.

You could also lay down some sod or plugs to speed things up a bit or go the route that many trampoline owners take by installing artificial turf instead. See this post for more under trampoline landscaping ideas.

Are There Trampolines that Don’t Kill Grass or Damage the Lawn?

Are you looking for the magical trampoline that doesn’t kill your grass or cause damage to your lawn?

Unfortunately, there is no special made solution quite yet. Since every situation is different, it’s hard to determine what trampoline will keep your grass safe.

As a rule of thumb smaller diameter trampolines are less disruptive to the lawn and will result in grass that’s easier to keep green because moisture and sunlight are less obstructed.

It is also worth mentioning that trampoline mats that are made from polypropylene material rather than rubber allow more sunlight to pass through. Older trampolines typically use rubber mats, which are very good at keeping the sun and moisture from your grass and eventually killing it.

Another feature that you might find desirable is a lightweight frame. Many find that lighter trampolines cause less sinkage and damage to their grass. A lighter build also means you’ll be able to move your trampoline around your yard much easier, which is a sure fire way to keep the lawn alive and healthy.

You Could Also Consider a Sunken Trampoline & Eliminate The Problem Entirely

If you really want a trampoline that doesn’t kill the grass, then you should consider paying to have your trampoline sunken. A sunken trampoline is mounted underneath the ground so that its jumping surface is level with the grass.

Sunken trampolines remove the need to worry about maintaining the landscape underneath as well as the risk of someone falling off. If you choose to go this route, then you’ll need to choose your spot wisely since the trampoline will be in the same spot until someone digs it out.

See my full grass growing guide here for more helpful tips – no opt-in needed.

How to Stop a Trampoline From Killing Grass

Unwanted dead grass patches where your trampoline sits don’t have to be a guarantee. There are a few simple things you can implement into your lawn maintenance routine to help prevent the grass from dying.

Move the Trampoline Regularly

One of the best ways to keep your grass healthy is by moving your trampoline around your yard on a regular basis. By doing this you allow the grass to have some breathing room.

Because your trampoline won’t be covering one specific spot of grass until it eventually dies, your yard will stay green & beautiful. Even if the grass suffers from some dryness and being nutrient deficient, when you move your trampoline it will get a chance to make a full recovery.

Take note that this is a great option if you have multiple locations in your yard that are level. Trampolines must be placed on a level surface to ensure a safe jumping experience. If this is not the case for you, you can hire landscapers to level out your yard.

Moving a trampoline might not be ideal depending on its weight and size. Some trampolines are lightweight enough for one person to move on their own. Many trampolines, however, are quite large and may require some helping hands if you have some.

Place a Sprinkler Underneath Your Trampoline

If moving your trampoline regularly isn’t going to cut it, then you can choose to place a sprinkler underneath it every once in a while. This is particularly useful if one of the main problems you are experiencing is dryness.

For those concerned about the integrity of their trampoline frame when exposed to water, there is nothing to worry about as long as the mat and frame covers are in place. Placing a sprinkler under your trampoline is completely safe and will not damage it in any way when the proper precautions are taken.

Find Some Reflective Lawn Decor & Put It Next to the Trampoline

This idea sounds almost laughable but it actually is a good option because many grass types can thrive in diffused light so long as it’s not totally blocked.

If you have a shiny lawn ornament, it doesn’t have to be a mirror either, when the sun hits it it will reflect in many different directs including under the trampoline. The light is all the grass needs to photosynthesize so any extra bit of sunlight helps, even if its just a bit of reflected light off a garden element.

One such example is this cool wind spinner I found on Amazon. It’s made from a shinny metal that will look great in your yard as decoration but will also serve the purpose of bouncing sunlight laterally in different directions, perfect for the task of getting a bit of extra light to go under the trampoline mat.

What Other Options Do I Have?

Sometimes trying to deal with the maintenance and upkeep yourself isn’t going to cut it. Whether you’re simply too busy or you feel that it’s a waste of time, there are other ways to deal with dying grass and preventing it from happening again in the future.

If you’ve been dealing with trying to fix the dead grass in your backyard and have finally had enough, then the following alternative options may be just what you’re looking for.

Place a Grass Mat Underneath

In some cases faking it doesn’t cut it. But when it comes to your trampoline, a synthetic grass mat can be a total lifesaver. It’s only a one-time investment into never needing to worry about the grass underneath your trampoline ever again.

Aside from removing maintenance, you also remove the need to move your trampoline around your yard. The benefit of keeping your trampoline in one place is that you don’t have to worry about shifting things out of place when you move it.

Install Organic Material Under Your Trampoline

Another alternative you can consider is installing a large base of organic material, such as mulch, sand, or bark, underneath your trampoline. This provides a soft, stable surface that will not only absorb impact but also remove the need to micromanage the grass underneath.

Creating an organic base for your trampoline is a one time process that you may find worth it. First, you need to dig up a 10-12 foot deep trench with a diameter allowing as much as 4-6 feet of space around your entire trampoline. Next, this trench is filled with your desired organic material. Simply install trimming around the edge to keep the material inside the area.

Place It Over Gravel

Placing your trampoline over gravel is another option that is overlooked. If you don’t have gravel in your yard, you can create a gravel patch large enough to place your trampoline on. Gravel is very low maintenance and removes the need to worry about the landscaping underneath your trampoline.

We’ve got more ideas for under trampoline landscaping here and a oat load of information on buying and caring for a trampoline here my guide to trampolines.

To Wrap Up Briefly

Trampolines are supposed to be fun for the whole family.

If you find that your trampoline is killing the grass in your yard, then it’s understandable if you’re upset. The good news is that it doesn’t have to stay like this.

Don’t allow some dead grass to ruin your day anymore. As long as you follow the recommendations above, you’ll be able to find a solution that works for you and your yard in no time. Then you’ll be able to really enjoy your trampoline!