Capacitive Soil Moisture Sensor
Capacitive soil moisture sensor. Measures relative soil moisture without corrosion from exposed electrodes.
Say it to PAL
“Tell me when my plant needs water.”
The code PAL writes
p.onSensorChange('qwiic-soil', 'moisture', (raw) => {
if (raw < 300) p.notify('Soil is dry! Raw: ' + raw);
});
await p.waitUntilStopped();When to pick it
The only option for soil moisture monitoring — essential for plant watering behaviors, and capacitive sensing avoids the corrosion problems of resistive sensors.
Good to know
- SPAN: about 200 (very dry) to about 2000 (very wet); ordinary damp soil reads about 300-500. Thresholds from the old 0-1023 model (e.g. 650) are wrong for this board; start a dry alert around 300 and calibrate in the person's own soil.
- Sensor tip must be fully buried in soil. Exposed tip reads max-dry.
- Not waterproof above the sensing tip — keep the board and connector above the soil line.
About it
A capacitive soil moisture sensor that measures relative moisture levels in soil. Unlike resistive sensors, capacitive sensing avoids electrode corrosion, extending sensor lifespan in wet soil. Suitable for plant monitoring, irrigation control, and agricultural applications. Output requires calibration for specific soil types.
Facts
Tested
Its driver works. We have not signed it off on a real board yet.
I2C address
The Capacitive Soil Moisture Sensor answers at I2C address 0x36. Whether the address can be changed is not recorded in this catalog.
Current
5 mA
The catalog lists a typical draw of 5 mA for the Soil Moisture, copied from the maker’s description and not measured by Palpable.
Board size
76.2 × 13.97 mm
The Soil Moisture board measures 76.2 × 13.97 mm and stands 7 mm tall with its parts. It has 2 mounting holes. These dimensions are from the maker’s mechanical drawing.
Free to reuse
Every fact here is open data under CC BY 4.0. Copy it into your own docs or code, and credit Palpable. Download it
This record was last changed on October 22, 2026.