Most low cost soil sensors are resistive style, which tend to oxidize and require constant recalibration. The Adafruit STEMMA Soil Sensor uses a superior capacitive measurement with no exposed metal, providing reliable moisture readings without harming your plants.

This sensor uses the ATSAMD10 chip’s built-in capacitive touch system to measure soil moisture, giving readings from about 200 (very dry) to 2000 (very wet). Additionally, it provides ambient temperature from the internal temperature sensor (+/- 2C accuracy).

Featuring an I2C interface via a 4-pin JST-PH connector, it can easily connect to most microcontrollers and single board computers. Compatible with Arduino and CircuitPython, it’s a no-solder sensor ready for your projects.

• Capacitive soil moisture sensing (non-resistive)
• Measures moisture from dry (~200) to wet (~2000)
• Ambient temperature sensing (+/- 2C)
• I2C interface with JST PH 2mm 4-pin connector
• Compatible with Arduino and CircuitPython
• Small, compact form factor without exposed metal

Note: This product includes the sensor only; a JST PH 2mm 4-pin cable is sold separately for connectivity.

Refer to the full guide for wiring, schematics, and code examples.