int water; //random variable void setup() { pinMode(3,OUTPUT); //output pin for relay board, this will sent signal to the relay pinMode(6,INPUT); //input pin coming from soil sensor } void loop() { water = digitalRead(6); // reading the coming signal from the soil sensor if(water == HIGH) // if water level is full then cut the relay { digitalWrite(3,LOW); // low is to cut the relay } else { digitalWrite(3,HIGH); //high to continue proving signal and water supply } delay(400); }