What to Do With a Soil Moisture Sensor?
Measure soil moisture, duh! This is a roundup of projects that progresses from simple readings to fully-automated greenhouses!
🌱 SparkFun Soil Moisture Sensor — Project Progression Roundup
In anticipation of a forthcoming product release (we won't tell you what, but we know you're smart), we decided to showcase projects that feature various forms of our soil moisture sensor - some projects are ours and some come from the community. The SparkFun Soil Moisture Sensor is one of those simple yet useful and fun tools that is a great entry point for makers, gardeners, and IoT project enthusiasts looking to expand their skills and keep their plants happy. Whether you’re building a smart garden, a plant health dashboard, or simply want your plants to tell you when they’re thirsty, these projects offer inspiration and practical guidance for getting the most from this little sensor.
All of these projects expand on the basic example of putting a soil moisture sensor in a pot or similar plant vessel and getting readings in the serial monitor on your computer. If you need help getting started, our Hookup Guide shows you how to do just that here! Now, let's move on to further functionality!
1. A Basic LED Example: Portable Moisture Display with LCD
Overview: In the Soil Moisture Sensor Hookup Guide, there’s a solid intermediate project that upgrades basic sensing to include a serial LCD display.
What It Does:
- Reads soil moisture using the SparkFun sensor attached to an Arduino or compatible board.
- Displays real-time moisture values on a compact LCD screen.
- Runs on portable power (like a 9 V battery).
Why It’s Cool: This turns a simple sensor into a standalone monitoring device you can move around your garden or plant shelf without needing a laptop or constant USB connection.
2. Slightly More Complicated, But More Cute: Smart Plant Care with Qwiic + OLED
Overview: A more recent SparkFun project takes advantage of the Qwiic Soil Moisture Sensor to build an intuitive feedback system. The guide walks you through integrating an OLED display to show expressive icons based on moisture levels.
What It Does:
- Uses the Qwiic version of the soil moisture sensor for solderless experience!
- Reads moisture levels and displays a happy/sad/neutral emoji on an OLED screen based on moisture thresholds.
- Demonstrates clear visual cues that make plant care fun and easy.
Why It’s Cool: Combining the Qwiic ecosystem and expressive feedback makes this great for workshops, classroom demos, and friendly desktop projects - no soldering required!
3. IoT Upgrade: Smart Moisture Monitoring with Blynk App
Overview: In the Smart Home Expansion Kit for Arduino 101 tutorial the soil moisture sensor is paired with a mobile dashboard using the Blynk IoT app. Note: the Arduino 101 is discontinued, but something like the Arduino R3 should work great.
What It Does:
- Measures soil moisture with the SparkFun soil sensor.
- Sends readings to the Blynk app via Bluetooth Low Energy (BLE).
- Displays moisture values and hydration status messages (“I’m Parched!”, “I’m Good!”, etc.) in real time.
Why It’s Cool: Turn your project into an IoT project — no screens required! You get live plant feedback right on your phone.
More Advanced Ideas from the Community!
Thirsty Flamingo Sensor
Overview: A playful project from the circuit.io team combining a piezo speaker and bunch of SparkFun parts to audibly alert when your plant needs water. So cute!
Smart Greenhouses
Overview: Obviously, the next step would be to build something like a smart greenhouse with a self-watering and lighting system. We've even seen some projects that utilize machine learning or AI to detect the color of leaves to figure out what your plant needs! While we won't be choosing any favorites, we recommend heading over to Hackster to go check them out!
As always, we can't wait to see what you make! Shoot us a tweet @sparkfun, or let us know on Instagram, Facebook or LinkedIn. Please be safe out there, be kind to one another! Happy hacking!
