Marie Katherine
Cheap and Easy Rain Catchment System for the Garden
Updated: Aug 31
This post contains affiliate links. If you use these links to buy something we may earn a commission. Thank you.
What is the best way to water your home garden?
A rainwater catchment system!
I installed one in my garden 3 years ago, and it’s been one of the best things I added! It saves the water bill, it’s easily accessible, and it’s environmentally! There are MANY ways to build a rainwater catchment system, but I like to keep it simple. This design is perfect for small gardens!
Want to learn more about what to do on a new homestead or in a new garden? Visit my post here!

Note:
Before deciding if you want to install a rainwater catchment system in your garden, take a look at your surroundings. Pay careful attention to any possible pollutants. For example, we are surrounded by farmland where we live, and in the summertime, several farmers will spray their crops with pesticides. This absolutely gets into the rainwater! When I see this happen, drain the rain barrel completely, and switch back over to using the hose-water to avoid the pesticides.
Materials needed:
1. A large trash can or a 100-gallon barrel.
I found mine used on Facebook marketplace for $10. A large outdoor trash can will also work though!
2. A flexible gutter downspout
3. A rain barrel spigot
4. Silicone
5. Concrete pavers
6. Sand
Tools need:
Here’s how to do it:
1. Choose a good location.
Choose a spot next to your house or a shed/outbuilding, directly underneath the downspout of the gutter system. If your house or outbuilding does not already have gutters, you will need to install them on the roofline yourself. This may seem intimidating, but it’s really not too difficult, especially if you’re already semi-comfortable with using tools such as a drill and a saw.
2. Level the ground and lay pavers/bricks to set the barrel on.
This is important because if the ground is not level, you risk the barrel tipping, splitting, or falling over once it’s filled with water. You will need to level a space of 2x2 feet to lay your pavers in a square.
The easiest way to do this is with sand, a 2x4 and a small level. Using the level, dig until it’s about 70% level. Then pour the sand on top, and use the 2x4 to scrape to level it until it is 100% level. Place your pavers or bricks on top. Sand is not necessary, but makes this job easier. Place your pavers directly on the sand, checking again to see that they are level in all directions.
3. Remove the lid.
If your barrel is closed at the top without a removable lid, you will need to remove the top. If you are using a trash can, simply turn the trash can lid upside, and cut a hole in the center to allow water to enter the barrel.
4. Using your drill and 1-inch hole bit, drill into the side of the barrel, close to the bottom.
Be sure to drill close to the bottom, so that there is not stagnant water sitting below this point, but where you can still attach a water hose.
5. Attach your 2-part spigot where you drilled the hole, sealing it on both sides with a line of silicone to make it water-tight.

6. Set your barrel on the pavers, and choose where to cut the gutter downspout.
The gutter extension is 21 inches long and can extend up to 60 inches. I recommend cutting about 21 inches above the top of your barrel. Do this carefully with a reciprocating saw, being careful to not damage your siding.
7. Attach your gutter extension to the gutter downspout, directing it to the barrel.
If you are using a 100-gallon barrel, and not a garbage can, you will need to cut an opening for the downspout to empty into.

8. This is the point that I called it done, BUT if you want to get fancy and prevent overflow, you can add a hose to the top of your barrel that runs out away from your house. This way, the barrel will not overflow, and water will be directed away from the house.
Note:
You will want to be mindful of preventing your barrel from freezing. Because I don’t need water for the garden in the winter, I simply open up the nozzle and let it drain as it rains. The ground directly in front of my barrel is not level and is raised around the house, meaning the water runs away from the house. If water pooling around your barrel (and subsequently around your house) is a concern, attach a hose, and run it away from your house, allowing the water to drain when it rains and prevent it from sitting, freezing, and overflowing in your barrel during the winter.
And that’s it! The easiest way to install a rainwater catchment system. I use mine almost daily after planting in the springtime and early summer to make sure my garden stays watered. It takes about an hour total to install if you have the right tools, and saves money on the water bill! Let me know what you think in the comments!
Want to learn more about gardening on a budget? Visit my post here!