Adafruit Simple Soil Moisture Sensor

The Adafruit Simple Soil Moisture Sensor is a gold-plated resistive sensor that measures conductivity between two prongs, providing easy soil moisture readings for micro:bit, Arduino, and other boards with analogue inputs.

Perfect for educational purposes, the Adafruit Simple Soil Moisture Sensor is a low-cost and easy-to-use device. This is a simple resistive-style moisture sensor, featuring two prongs that measure the conductivity between them. We gold-plated the prongs to reduce the risk of oxidation – if you see build-up on the prongs, clean them off with a dish-scrubber to keep the sensor going.

While not as advanced as a capacitive or frequency-based sensor, these are easy to use! We’re stocking this sensor for folks who want to use it with a micro:bit or Arduino, or other board with an analog input. It won’t work with a Raspberry Pi because it doesn’t have analog inputs; for that, use one of our capacitive sensors.

Getting started is super easy!

•  When using with a micro:bit you’ll need some small alligator clips.  Connect the GND pad from the ‘bit to the GND pad on the sensor. Connect the 3V pad to the 3V pad. Then connect the 0 pad on the ‘bit to the OUT pad on the sensor (you can also use 1 or 2 pads on the ‘bit). Then, on the micro:bit read the analog value. When the soil is dry, the reading will be under 100. As the soil gets wetter, it will rise to 1000. 
• On an Arduino, connect 3V to the 3V output pin (or 5V if there’s no 3V pin) and GND to ground. You can either use alligator clips to pins or a JST SH to a 3-pin cable. Then connect the OUT to A0 or another analog input. When you use analogRead(), you’ll see dry soil at < 100 and wet soil > 600.

Either way, no soldering is required!

Please note: This is just the sensor; you’ll also need alligator clips or a JST-SH cable to connect to it! 

Resources

• Primary Guide: Adafruit Simple Soil Moisture Sensor

Package Contents

• 1x Adafruit Simple Soil Moisture Sensor – For micro:bit, and more.