SparkFun Qwiic Soil Moisture Sensor

SparkFun Qwiic Soil Moisture Sensor makes it easy to monitor moisture levels in soil using a Qwiic cable or standard pins. With a gold-plated finish for longer life, it’s a simple, durable solution for sensing water content in plant pots.

The SparkFun Qwiic Soil Moisture Sensor is a simple breakout for measuring the moisture in soil and similar materials. The soil moisture sensor is pretty straightforward to use. The two large, exposed pads function as probes for the sensor, together acting as a variable resistor. The more water in the soil, the better the conductivity between the pads will be, resulting in lower resistance and a higher SIG output.

This version of the Soil Moisture Sensor features a Qwiic connector, making it even easier to use.

To get the SparkFun Soil Moisture Sensor functioning, simply connect the VCC and GND pins to your Arduino-based device (or a compatible development board). You will receive a SIG out, which will depend on the amount of water in the soil.

One commonly known issue with soil moisture sensors is their short lifespan when exposed to a moist environment. To combat this, we’ve had the PCB coated in gold finishing (ENIG, or Electroless Nickel Immersion Gold).

The video below shows the original non-Qwiic version of the sensor:

Features

• Measures soil moisture using conductivity between exposed probes
• Qwiic connector for easy plug-and-play I2C integration
• Analog SIG output varies with soil water content
• Gold-plated ENIG PCB finish for improved corrosion resistance
• Simple 3-pin connection: VCC, GND, and SIG
• Designed for use with Arduino and compatible development boards

Resources

• Schematic
• Eagle Files
• Hookup Guide
• Libraries:
  • Arduino
  • Python / MicroPython / CircuitPython
• GitHub Hardware Repo

Package Contents

• 1x SparkFun Qwiic Soil Moisture Sensor