How to measure soil moisture over a cellular connection

Whether you garden as a hobby or make your living farming, you need to pay attention to the growing conditions of your plants and crops. And the faster you can react to these conditions, the better your yields.

The Cellular IoT Soil Moisture Monitor reference design aims to be a proof-of-concept for operations that need far-flung sensors throughout an operation that can report back to the cloud on regular intervals. The hardware and software is ready to use, and all components can be ordered at Digikey. If you start with the recommended components of this design you can quickly prototype your own ag-tech solution, and customize where and when necessary.

Parts list

Monitoring soil moisture level, ambient temperature, pressure, humidity, and RGB light intensity allows farmers to take action before the plant’s demise. The Soil Moisture Monitor design takes advantage of the ease of use of the Nordic nRF9160 DK and cellular network connection, sending sensor data to Golioth’s Cloud at changeable periodic intervals.

You should buy all the necessary components from DigiKey (listed above), load the precompiled firmware image, and you are set for success to start sending data to the Golioth Cloud. You benefit from the well-tested software running on the nRF9160 DK and can immediately connect to the Golioth Cloud with the free Prototype tier. Connect up to 50 devices at no cost, utilizing all the Device Management Features Golioth has to offer, like Over-The-Air Firmware Updates, LightDB State, LightDB Stream, Logging, Settings, and Remote Procedure Calls.

If you want to deep dive into Zephyr RTOS and expand this Reference Design, head to the project’s GitHub page, clone the repository, and modify the open-source code to truly make this your own customizable device.


Most of the products in your list are not avaialble where I live. Can I use low cost moisture sensors like these which are usually from dfrobot or some non-branded chinese component shops?

here is moisture sensors we do carry. Click Here

Hey bidrohini,

This project uses the MikroE Hydro Probe Click that has the MCP3221 ADC to convert moisture level to a digital value. If you would to use the The Cellular IoT Soil Moisture Monitor reference design as is, the Soil Moisture sensor of your choice must have the same ADC on board. A good thing to note is that there is no Zephyr support for MCP3211 ADC at the moment, and the data from the ADC register is read using the I2C read calls in the app_work.c file.

If you were to choose a Soil Moisture sensor with a different ADC, make sure to implement the communication with the sensor and read the appropriate registers.

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Thank you so much, sir.