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hanez.org · SensorsCurated

Measuring plant moisture with an Arduino

Summary

Johannes reads a cheap soil moisture sensor every two seconds through an analogue Arduino input. The sensor is connected to input A0. The serial output runs at 9600 baud.

Ideas

  • analogRead delivers a raw value from the sensor.
  • The serial interface makes measurements visible without an additional display.
  • A two-second interval is enough for slowly changing soil moisture.

Insights

  • Small sensor projects become understandable more quickly with traceable raw data.
  • Resistive sensors that are permanently powered can corrode and change their readings.

Facts

  • The example code waits 2000 milliseconds between measurements.

Recommendations

  • Only power the sensor during the measurement to reduce corrosion.
  • Calibrate the dry and wet limits with the soil you actually use.

References

Read the original article on hanez.org

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