Greenhouse Automation

//Libraries included
#include <LiquidCrystal.h>
#include <Adafruit_Sensor.h>
#include <DHT.h>
#include <DHT_U.h>

//LCD digital pins connection
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
//DHT11 digital pins connection and dht sensor type
#define DHTPIN 13
#define DHTTYPE DHT11
DHT dht(DHTPIN, DHTTYPE);
//4Relay module digital pins connection
#define PIN_RELAY_1 7   // the Arduino digital pin 7 - IN1 pin of relay module
#define PIN_RELAY_2 8   // the Arduino digitall pin 8- IN2 pin of relay module
#define PIN_RELAY_3 9   // the Arduino digital pin 9 - IN3 pin of relay module
#define PIN_RELAY_4 10  // the Arduino digital pin 10 - IN4 pin of relay module
//define soil moisture sensor analog pin A0
const int Soil_Pin = A0;
const int Ldr_pin = A1;

void setup() {
  Serial.begin(9600);
  lcd.begin(16, 2);  // initialize the LCD
  dht.begin();       // initialize the dht sensor
  // initialize digital pins as an output.
  pinMode(PIN_RELAY_1, OUTPUT);
  pinMode(PIN_RELAY_2, OUTPUT);
  pinMode(PIN_RELAY_3, OUTPUT);
  pinMode(PIN_RELAY_4, OUTPUT);
  //ldr read as input
  pinMode(Ldr_pin, INPUT);
}

void loop() {
  // wait between measurements.(500ms = 0.5 Second)
  delay(500);
  float temperature = dht.readTemperature();  // read temperature in Celsius  // temperature in Celsius
  float humidity = dht.readHumidity(); //read humidity //humidity declaration

  //ldr read as analog
  int ldr_Value = analogRead(Ldr_pin); 

  //soil sensor data in percentage
  float moisture_percentage;
  int sensor_analog;
  sensor_analog = analogRead(Soil_Pin);
  moisture_percentage = (100 - ((sensor_analog / 1023.00) * 100));
  
// Plot live data in the Arduino ide serial plotter 
  Serial.print(moisture_percentage);
  Serial.print(" "); // a space ' ' or  tab '\t' character is printed between the two values.
  Serial.print(temperature);
  Serial.print(" "); // a space ' ' or  tab '\t' character is printed between the two values.
  Serial.println(humidity); 
  Serial.print(" "); // a space ' ' or  tab '\t' character is printed between the two values.  
//  lcd screen display order
  lcd.setCursor(0, 0);
  lcd.print("M %");
  lcd.setCursor(0, 1);  
  lcd.print(moisture_percentage);
  lcd.setCursor(6, 0); 
  lcd.print("Tc");
  lcd.print((char)223);//shows degrees character  
  lcd.setCursor(6, 1);
  lcd.print(temperature);
  lcd.setCursor(12, 0);
  lcd.print("H %");
  lcd.setCursor(12, 1);
  lcd.print(humidity);
// Conditional statment to control the relays (Greenhouse systems)

  if (moisture_percentage < 60.00){
    digitalWrite(PIN_RELAY_1, LOW);    // turn in1 ON 
  } else {
     digitalWrite(PIN_RELAY_1, HIGH);  // turn in1 OFF 
  } 
  if (temperature < 20) {
    digitalWrite(PIN_RELAY_2, LOW);    // turn in2 ON
  } else {
     digitalWrite(PIN_RELAY_2, HIGH);  // turn in2 OFF
  }
  if (temperature > 30) {
    digitalWrite(PIN_RELAY_3, LOW);    // turn in3 ON
  } else { 
      digitalWrite(PIN_RELAY_3, HIGH); // turn in3 OFF
  }
  if (ldr_Value < 300) {
    digitalWrite(PIN_RELAY_4, LOW);    // turn in4 ON
  } else {
    digitalWrite(PIN_RELAY_4, HIGH);   // turn in4 OFF
  }
 
  delay(2000);  // wait after loop for 2 Seconds  

}