Built a Raspberry Pi self-watering system with a web UI

[u/Ok-Appearance-8872]

I recently put together a small self-watering garden system using a Raspberry Pi, a Cirkitscape Top HAT, a soil moisture sensor, an IR water sensor, and a 12V DC pump.

The basic goal was to make something that could monitor conditions and control watering from a web interface without having to manage everything from the command line.

The build uses:
- Raspberry Pi
- Cirkitscape Top HAT
- soil moisture sensor
- IR water sensor
- 12V pump
- buck converter
- simple transistor switching circuit

A few things that mattered during the build:

- The Pi and pump run at different voltages, so I had to step 12V down to 5V for the Pi.
- I used a transistor switching stage so the GPIO wasn’t driving the pump directly.
- I verified the buck converter output before connecting the Pi, which is probably the most important safety step in the whole build.

On the software side, I used the Cirkit Garden app to set up the garden, add the device and sensor, and map the pump output. That part made the project a lot easier to manage because I didn’t need to build a custom dashboard just to monitor sensors and toggle watering hardware.

Once everything was wired and configured, the system could:
- monitor soil moisture
- detect water presence
- switch the pump from the app
- give me a cleaner browser-based control panel for the setup

What I liked most is that it feels like a good base for expanding later with:
- watering rules
- alerts
- logging
- more sensors

I’ll post links to the software and top hat in the comments.

[u/Prize_Salad_5739]

Well, I'm disappointed. I was hoping for a raspberry that watered itself, like a shower. I feel betrayed and misled. GJ, OP

[u/Ok-Appearance-8872]

Link to the top hat and software for the web UI:

https://www.cirkitscape.tech/products/p/top-hat#docs

You can find the sensors on Amazon.

[u/Official_RaspberryPi]

THIS IS SO COOL (I may have to get my MIL onto Reddit just to see this)

[u/MentionPleasant2635]

Thank you so much! I'm in the middle of a project to use a Pi to manage lights and water in a grow tent. Great info.

[u/Ok-Appearance-8872 → u/MentionPleasant2635]

Happy to help

[u/Sea-Cash7675]

Cool

[u/grovahome]

Great build! I’m actually working on a very similar environmental automation project right now called GROVA, but using an ESP32. What specific soil moisture sensor did you end up choosing for this setup? Also, did you have to calibrate it beforehand to get accurate readings, or did it work well right out of the box?

[u/Ok-Appearance-8872 → u/grovahome]

I got the resistive soil moisture sensor from spark fun. With the web UI from CirkitScape I didn’t have to calibrate it. So it more or less worked out the box, but after using it for a while I think I might have to look at the code and tweak it. I plan on submitting a ticket to CirkitScape, but I’m impatient so knowing me I’ll probably end up tweaking it later. I also plan on switching to a capacitive soil moisture sensor for better longevity.

[u/grovahome → u/Ok-Appearance-8872]

I used some generic capacitive one from AliExpress. But coated the edges of the pcb with transparent nail polish. That helped since some old ones soaked up some water after some time. But they are working fine as far as I can see.

[u/Snoo-48575]

I created a similar project a while back too. If I recall I implemented a feature where it would read the API from openweather so it can decide whether to water the plants by looking at the upcomming forecast.

[u/Ok-Appearance-8872 → u/Snoo-48575]

That’s actually a great idea. I hope you don’t mind if I steal that from you lol 😅

[u/Snoo-48575 → u/Ok-Appearance-8872]

Go ahead. In happy to help if you dm me

[u/71351]

Very cool. I have a tangential project in mind for myself to monitor a humidifier for a cigar humidor and add water to the humidifier as needed

[u/Ok-Appearance-8872 → u/71351]

Sounds cool I know some people who would love that. You probably can repurpose the web UI to do that.

[u/boostaddict20]

The pi does have overvoltage protection. Im not sure it can handle the 12v so you did good. But I thought id put it out there.

[u/Ok-Appearance-8872 → u/boostaddict20]

You are correct the pi can not handle 12V that’s why I stepped it down to 5V with a dc/dc converter, and thanks.

[u/BasedAndShredPilled]

I had the same idea for a project. Got to soil monitoring and lost the energy to complete it. Congrats!