Gravity: Analog Soil Moisture Sensor for Arduino & Raspberry Pi

Gravity: Resistive Analog Soil Moisture Sensor is designed for educational settings and hobbyist applications, making it perfect for short-term monitoring projects in stable indoor environments. This sensor operates on a power supply of 3.3V or 5V and outputs a voltage signal ranging from 0 to 4.2V, allowing for easy integration with popular platforms such as Arduino and Raspberry Pi. Utilizing a resistive sensing method, it detects soil moisture through changes in resistance, providing an easy and cost-effective option for basic electronics courses and scientific demonstrations.

The new soil moisture sensor uses Immersion Gold which protects the nickel from oxidation. Electroless nickel immersion gold (ENIG)  has several advantages over more conventional (and cheaper) surface platings such as HASL (solder), including excellent surface planarity (particularly helpful for PCB's with large BGA packages), good oxidation resistance, and usability for untreated contact surfaces such as membrane switches and contact points.

This soil moisture Arduino sensor uses the two probes to pass current through the soil, and then it reads that resistance to get the moisture level. More water makes the soil conduct electricity more easily (less resistance), while dry soil conducts electricity poorly (more resistance).

This sensor will be helpful in reminding you to water your indoor plants or monitor the soil moisture in your garden.

To ease the difficult of using this sensor,  a Gravity Interface is adapted to allow plug&play.   The Arduino IO expansion shield is the best match for this sound senor connecting to your Arduino. As this sensor can work at 3.3V which make it compatible with Raspberry Pi, Intel Edison, joule, and curie.

Note:

For more detailed insights on selecting the most suitable sensor, refer to the guide on [How to Select the Best Soil Moisture Sensors for Agriculture and Research Lab].

If you are going to place the sensor to very humid soil, that would make it very easy to get the sensor surface erosion within several days, hence we suggest to use this one Analog Capacitive Soil Moisture Sensor- Corrosion Resistant instead.