Once you have dug a pit in the ground for an inground trampoline, the next step is to put something down to line the pit. But what do you put down? What do you put under in an inground trampoline?
The best thing to put under an inground trampoline is pea gravel and weed matting. This will stop weeds growing under your trampoline and allow good water drainage. Depending on your drainage and soil type, you may also need a pump to remove rainwater before it becomes stagnant.
Let’s go through some of the finer points of what to put under an inground trampoline, so that you’ve got all you need to make your inground trampoline a long-term success.
What To Put Under An Inground Trampoline?
When you have an inground trampoline, it’s a good idea to stop weeds growing, whilst also ensuring that the water doesn’t pool in the pit. For the water, this covers both rainwater as well as ground water that may seep into the pit.
For an inground trampoline pit, I recommend using pea gravel and weed matting as a barrier layer that also helps with drainage. Depending on your soil type and how well it drains, I would also look at installing a pump to help with removing water.
The pump can be either permanently installed to go on automatically whenever the water hits a certain level, or can be turned on manually when you notice the water in the pit or when it is raining. The choice of pump will depend on your budget and your level of need for convenience.
I’ll go through each of these elements, the pea gravel, the weed matting and the pump in more detail. Along the way, I’ll also share information about what you shouldn’t put under an inground trampoline.
What Is Pea Gravel?
Pea gravel is a small smoothed pebble about the size of a pea that comes from tumbling crushed rock in a big mill. The tumbling process knocks off the rough edges, leaving it smoothed. And of course, on average it is around the size of a pea, around 3/8”.
Why Is Pea Gravel Good Under An Inground Trampoline?
Pea gravel is good under an inground trampoline as it helps prevents weeds, as well as allowing quick drainage of rainwater and groundwater in suitable soils.
It can also become fairly compact, which lets you level the trampoline in case the ground isn’t exactly flat where you’ve dug it out.
Whilst you can use crushed rock under a trampoline, I’ve suggested pea gravel as it won’t cut the weed matting. If your inground trampoline has legs, the legs will be sitting on the weed matting and gravel. Pea gravel is very smooth. As the kids jump on the trampoline, the force gets distributed down through the legs to the earth. You want to have smooth gravel, not sharp-edged gravel, pushing down on the weed matting so that it doesn’t get cut.
Do Inground Trampolines Attract Weeds?
Inground trampolines attract weeds if the soil stays moist, and they can get enough sunlight.
If weeds are allowed to grow under a trampoline, they will grow up toward the sunlight. Weeds are successful because they are fast-growing, resilient and robust. They will come up through the matting and springs. If the weeds are under the mat itself, it might impact the quality of your bounce.
And when the weeds die back, they may form a mass of organic matter in the inground trampoline pit. This will rot, and smell terrible.
What Is Weed Matting?
Weed control using black weed matting is fairly common. Weed matting is generally made of a long wide strip of polyethylene plastic. It might be thermally spunbonded, woven or needlepunched to give small holes for drainage and soil health. The woven or spunbonded will suit you best in the long run.
Why Is Weed Matting Good Under An Inground Trampoline?
Weed matting is good under an inground trampoline as it will prevent weeds from growing, whilst still allowing drainage of rainwater or groundwater. You definitely don’t want either weeds or a pool of water under your trampoline.
Why Shouldn’t You Use Contractor’s Sheeting Under Your Trampoline?
Contractor’s sheeting is not a good option as it will allow the water to collect in a pool and become stagnant.
This sheeting is a hard-to-break thick layer of plastic, so at first it seems like it might be a good choice. Unfortunately, the lack of holes in the sheeting means that there is nowhere for rainwater to go after it rains.
Why Use A Pump Under An Inground Trampoline?
When water builds up under a trampoline, it becomes dangerous fairly quickly. You want a pump to remove it.
An enterprising toddler can slip through the gap between the springs and end up in the pit. As well as being uncomfortable, any water more than a couple of inches deep can be unsafe for a toddler.
In a poor scenario for your inground trampoline bouncing, if the water builds up too high, you will hit the pool of water under the mat when you bounce. This will absolutely stop you from jumping high and having fun on your trampoline.
If the water has the chance to pool, it can also become a breeding ground for mosquitoes in the right climate. And if you are in a drier area, the water under an inground trampoline is attractive to rodents and snakes as a source of drinking water.
A pump will help to remove any buildup of water under your inground trampoline. There are many types of pumps, configurations for good drainage, as well as considerations around soil type and lay of the land.
Click here for more information on inground trampolines and pumps.
In Summary
Under an inground trampoline, you should put pea gravel and weed matting. This will help with drainage whilst still keeping weeds to a minimum. You may also need a pump if the water can’t drain well in your soil. You definitely don’t want a pool of water under your inground trampoline.
