const int AirValue = 733; // you might need to calibrate this number, instruction is down below

const int WaterValue = 355; // you might need to calibrate this number, instruction is down below

const int DrySoilMoisturePercentage = 50;

const int SoilMoisturePin = A0;

const int RelayPin = D2;

int soilMoistureValue = 0;

int soilmoisturepercent = 0;


void setup() {

  Serial.begin(9600);

  pinMode(SoilMoisturePin, INPUT);

  pinMode(RelayPin, OUTPUT);

  digitalWrite(RelayPin, HIGH);

}


void loop() {

  soilMoistureValue = analogRead(SoilMoisturePin);

  soilmoisturepercent = map(soilMoistureValue, AirValue, WaterValue, 0, 100);

  Serial.print(soilmoisturepercent);

  Serial.println("%");

  if (soilmoisturepercent <= DrySoilMoisturePercentage) {

    Serial.println("Water pumps running...");

    digitalWrite(RelayPin, LOW);

    delay(1000);

    }

  if (soilmoisturepercent >= DrySoilMoisturePercentage) {

    Serial.println("Water pumps stopped...");

    digitalWrite(RelayPin, HIGH);

    delay(1000);

    }

}