Soil Hygrometer Moisture Water Sensor for Arduino

The Hardware

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MoistureProbe

The Wiring

  • VCC = 5V
  • GND = GND
  • DO = Digital 2
  • AO Analog 1
  • MoistureProbe2

The Code

    const int VAL_PROBE = 1; // Analog pin 0
    void setup() {
    Serial.begin(9600);
    }
    void loop() {
    int moisture = analogRead(VAL_PROBE);
    Serial.println(moisture);
    delay(100);
    }

The Output

  • Mid Air = 667
  • Soil (in a cup after 3mm Rain) = 539
  • Tongue = 319
  • Soil (in a cup with a few teaspoons of water added (tap water)) = 284
  • Soil (in a cup with a maximum saturation (tap water)) = 162
  • Soil (in a cup with a maximum saturation (tap water with salt added)) = 59