water sensor + relay arduino

int lightPin = 0; // Analog Input
int threshold = 500;

// the setup routine runs once when you press reset:
void setup() {
  // initialize the digital pin 13 as an output.
  Serial.begin(9600);
  pinMode(13, OUTPUT);

}

// the loop routine runs over and over again forever:
void loop() {
Serial.println(analogRead(lightPin));

    if(analogRead(lightPin) > threshold ){
        digitalWrite(13, HIGH);
        Serial.println("high");
    }else{
        digitalWrite(13, LOW);
        Serial.println("low");
    }

  delay(1000); // wait for a second
}