How to Make a Self-Watering Garden Bed

How to Make a Self-Watering Garden Bed

Sharing is caring!

Whether you live in the city or in the country, one of the best things you can do is to have your own garden. Flowers and regular plants are great, but what you should be doing is growing your own veggies and herbs.

The fact of the matter is that when you grow your own herbs and produce, you can control exactly what goes into it, as opposed to purchasing expensive and chemical-filled veggies from your local stores. It’s much healthier, it’s more reliable, and you can choose exactly what you want to grow.

That being said, one of the most important aspects of growing any kind of plant is water, but of course, you might forget to water your plants, and that’s not good. To make life a bit easier for you, try making a self-watering garden bed.

This is a type of garden bed that has a water reservoir built into the bottom of it. When correctly built, as long as you fill the reservoir on a regular basis, you don’t have to worry about your plants being under or overwatered. Right now, we want to take you on a step-by step tutorial on how to build a self-watering garden bed.

Required Tools and Equipment

First off, before you can get started building a self-watering garden bed, you will need to have the needed tools and materials. There isn’t too much to gather, and if you are smart about it, you can recycle old materials you have laying around to keep the cost at a minimum.

  • Wood and screws
  • Food-safe waterproof liner
  • Overflow valve
  • Water stem – (something like a PVC Pipe)
  • Water reservoir materials – (can be a garden reservoir kit or something like gravel)
  • Corner brackets
  • A staple gun
  • Utility knife
  • Circular saw – (Can be a hand saw too)
  • Drill
  • Tape measure
  • Bubble level

Step 1: Choosing the Right Location

Before you can get started, you first need to select the right location for it. This is very important if you expect your garden to grow properly.

You need a location that will provide your veggies and herbs with at least 6 to 8 hours of direct sunlight per day. There are some crops that can be grown with less light, things like kale and spinach, which can survive on as little as 4 hours of sunlight per day. The more sun your garden bed gets, the better.

You always want a location that is close to a water source. Of course, the whole point of a self-watering garden is to have to water it less frequently, but you will still have to fill the water reservoir on occasion.

Make sure to select a location that you frequent a lot or that you can easily see from your house. This will ensure that you don’t forget to look after it.

Your location also needs to be level and flat; for the water reservoir to work properly, it needs to be on flat and level ground. If you don’t have access to level ground, you may have to dig down or build upwards.

Step 2: Building the Frame

The first step is to start building the frame of the self-watering garden bed. If you are using gravel for the reservoir, then you can go with any size you see fit, but if you are using some sort of self-watering reservoir kit, these usually come in 1 x 1 foot squares, so you will need to keep this in mind.

For instance, if you are making a garden that is 5 x 5 feet, make sure to put the wooden frame on the outside of that 5 x 5 foot measurement, so the inside is actually 5 x 5 feet (the wood takes up space too). It’s not 100% essential to do this, but it will help. You may want to use corner brackets to keep the corners together.

How to Make a Self-Watering Garden Bed

Step 3: Preparing the Liner

The next step is to prepare the garden bed liner, the thing that will stop the water from flowing out of the bottom of the reservoir. You will need to do some measuring here. The liner should cover the bottom of the reservoir and it should go up the walls at least 6 to 8 inches on all sides.

To get the right length and width measurements for cutting the liner, just add the width of the garden bed to the height which you want the liner to go up both sides, and then do this for the length as well.

Once you have measured, you can then use something like a utility knife to cut the liner. It is then a good idea to pre-fold the liner so it already has creases in it once you go to put it in the frame.

Step 4: Drilling the Overflow Valve Hole

Now you need to drill the hole for the reservoir’s overflow valve, because you want the reservoir to fill up, but not to the point where it floods the soil on top.

How far up you put the overflow valve, and therefore where you drill the hole, will depend on the depth of your reservoir. If the reservoir is 6 inches deep, drill your hole just slightly above the 6 inch mark. Make sure the hole you drill is the same size as the piping being used.

Step 5: Install the Liner

Now it is time to install the liner. Be sure to not puncture it when doing this, or else it will become useless. First off, ensure that the liner is tucked into the corners and has a good fit, as well as that the liner goes to the top of the walls.

Get your stapler or staple gun and staple the liner to the frame, about 1 inch from the top. Try to use a pattern that looks nice! You can use a utility knife to trim off excess liner from the top.

Step 6: Install the Overflow Valve

Use your finger and gently press around on the frame of the garden bed to find the hole which you cut out for the overflow valve. Once you find the hole, cut a very small X into the center of it, and then push the piping for the overflow valve through the hole. Whatever type of piping or valve you are using, make sure it is properly installed.

Step 6: Install the Reservoir

If you are using a garden DIY kit where the reservoir comes in 1 x 1 foot cubes, just snap together the appropriate amount and lay them in the bottom of the garden bed. If you are using rock or gravel instead, now is the time to insert it.

Remember that the reservoir material should sit slightly above the overflow valve to allow for proper drainage. You want at least 3 inches of reservoir depth for every 10 inches of soil on top.

Step 6: Install the Water Stem

The water stem is where you will pour water down into to fill the reservoir.

If you are using DIY garden wells, make sure to drill the hole for the water stem (usually just something like a PVC pipe) outside of the frame; if you have already inserted the wells, take them back out do drill the hole for the water stem.

If you are using gravel or rock as your reservoir material, place the pipe so it reaches the top of the reservoir. It will then be held in place by the soil you use for the plants.


As you can see, although building a self-watering garden bed does take a bit of work, it’s not all that hard, and we think that you will be very pleased with the results.

Subscribe now to get free discount coupon code. Don't miss out!
    I agree with the term and condition