Published January 10, 2019 © CC BY

Automatic Plant Hydrator

Fed up of forgetting to water your plants every day? Build this project and never worry about doing it again.

BeginnerFull instructions provided1 hour1,182

Things used in this project

Hardware components

arduino UNO

LCD

potentiometer

SparkFun Soil Moisture Sensor (with Screw Terminals)

pump

PCBWay Custom PCB

Story

Fed up of having to remember to water your plant? or Worried your watering it to much or too little? If so follow the instructions below and never have to worry about it again.

This project will use an Arduino Uno but if you wanted to you could use any of the Arduino family. It will use an LCD to display at what moisture level the pump turns ON and how long the pump will stay ON for.

I used a generic moisture sensor but you could any moisture sensor you like. I used a cheap DC pump from Ebay they cost about £3 and you can find the one I used here. You will need to solder wires to the moisture sensor and you may also need to solder wires to the pump dependent on what one you use.

Below is the schematic of how to connect all the parts to the Arduino. The Arduino will have to be powered when being used so I used a USB power bank. (In the schematic I have forgotten to add a transistor for the motor so you will need to remember to add this)

Schematic

Once everything is connected you will need to upload the code. connect your Arduino to a computer using a USB cable and open the code in the Arduino IDE and upload it to the Arduino. I am just learning to code so if there are any problems let me know.

After the Arduino is programmed you will want to protect the circuity from the elements to do this I used a plastic lunch box and drilled holes in the side for the wires for the sensor and motor to pass out of, I then sealed the hole using hot glue.

You can then power up your device using a battery and set the settings to match your requirements. Then seal up the box by snapping the lid in place and place your sensor into the soil. then connect a tube from one side of the pump and place it into a container of water and then connect another piece of tube to the other side of the pump and place it near to the plant you want to water.

Now once every thing is set up just wait and when the moisture level in the soil goes below your setting the pump will turn on and water the plant. You may need to experiment with the values of the setting to suit your needs.

Acknowledgement

I thank PCBWay & LCSC Electronics for the partnership.

PCBWay Is a cheap reliable service where you can get your PCBs manufactured. All the PCBs are high quality and the engineers are very helpful and will resolve any problems you may have quickly. Sign up today and get a $5 welcome bonus. Check Out PCBWay Hackster page.

LCSC Electronics Is China's leading Electronic Components Distributor. LCSC sells a wide variety of high quality electronic components at low prices. With over 150, 000 parts in stock they should have the components you need for your next project. Sign up today and get $8 off on your first order.

Website

Check out more of my other projects on my website.

Untitled file

// Adam Redfern    Ohmega elctronics    09/01/2019


#include <LiquidCrystal.h>  // initialize the library by associating any needed LCD interface pin

const int sensor = A0;  // connect the input from the moisture sensor.
const int pump_timing = A1;  // connect the potentiometer to set the pump timings.
const int Moisture_trigger = A2;  // connect the potentiometer to set the moisture trigger.
const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2;  //set the pins for the LCD
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);   //set the pins for the LCD
int pump = 7 ; // connect the positive of the pump to this pin

void setup(){  
  pinMode(pump, OUTPUT);  //set the pump as an output 
  lcd.begin(16, 2);  //set up the LCD's number of columns and rows
}

void loop() {

int pump_value = analogRead(pump_timing); // Read the value from the potentiometer 

(if (pump_value 0 && pump_value < 99)
{
if (sensor > Moisture_trigger)
  digitalWrite(pump, HIGH);  //turn the pump on
  delay(2000);  //how long to keep the pump on for 
  digitalWrite(pump, LOW);  //turn the pump on
}
else if (pump_value >= 100 && pump_value < 199)
{
if (sensor > Moisture_trigger)
  digitalWrite(pump, HIGH);  //turn the pump on
  delay(4000);  //how long to keep the pump on for 
  digitalWrite(pump, LOW);  //turn the pump on
}
else if (pump_value >= 200 && pump_value < 299)
{
if (sensor > Moisture_trigger)
  digitalWrite(pump, HIGH);  //turn the pump on
  delay(6000);  //how long to keep the pump on for 
  digitalWrite(pump, LOW);  //turn the pump on
}
else if (pump_value >= 300 && pump_value < 399)
{
if (sensor > Moisture_trigger)
  digitalWrite(pump, HIGH);  //turn the pump on
  delay(8000);  //how long to keep the pump on for 
  digitalWrite(pump, LOW);  //turn the pump on
}
else if (pump_value >= 400 && pump_value < 499)
{
if (sensor > Moisture_trigger)
  digitalWrite(pump, HIGH);  //turn the pump on
  delay(10000);  //how long to keep the pump on for 
  digitalWrite(pump, LOW);  //turn the pump on
}
else if (pump_value >= 500 && pump_value < 599)
{
if (sensor > Moisture_trigger)
  digitalWrite(pump, HIGH);  //turn the pump on
  delay(12000);  //how long to keep the pump on for 
  digitalWrite(pump, LOW);  //turn the pump on
}
else if (pump_value >= 600 && pump_value < 699)
{
if (sensor > Moisture_trigger)
  digitalWrite(pump, HIGH);  //turn the pump on
  delay(14000);  //how long to keep the pump on for 
  digitalWrite(pump, LOW);  //turn the pump on
}
else if (pump_value >= 700 && pump_value < 799)
{
if (sensor > Moisture_trigger)
  digitalWrite(pump, HIGH);  //turn the pump on
  delay(16000);  //how long to keep the pump on for 
  digitalWrite(pump, LOW);  //turn the pump on
}
else if (pump_value >= 800 && pump_value < 899)
{
if (sensor > Moisture_trigger)
  digitalWrite(pump, HIGH);  //turn the pump on
  delay(18000);  //how long to keep the pump on for 
  digitalWrite(pump, LOW);  //turn the pump on
}
else if (pump_value >= 900 && pump_value < 1023)
{
if (sensor > Moisture_trigger)
  digitalWrite(pump, HIGH);  //turn the pump on
  delay(20000);  //how long to keep the pump on for 
  digitalWrite(pump, LOW);  //turn the pump on
}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//This section selects what moisture percentage will be displayed on the LCD dependent on the value of the potentiometer// 
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

Moisture_trigger = analogRead(Moisture_trigger); // Read the value from the potentiometer 

(if (Moisture_trigger 0 && Moisture_trigger < 99)
{
lcd.setCursor(0, 1);  //display on bottom line of LCD
lcd.print("10%");
}
else if (Moisture_trigger >= 100 && Moisture_trigger < 199)
{
lcd.setCursor(0, 1);  //display on bottom line of LCD
lcd.print("20%");
}
else if (Moisture_trigger >= 200 && Moisture_trigger < 299)
{
lcd.setCursor(0, 1);  //display on bottom line of LCD
lcd.print("30%");
}
else if (Moisture_trigger >= 300 && Moisture_trigger < 399)
{
lcd.setCursor(0, 1);  //display on bottom line of LCD
lcd.print("40%");
}
else if (Moisture_trigger >= 400 && Moisture_trigger < 499)
{
lcd.setCursor(0, 1);  //display on bottom line of LCD
lcd.print("50%");
}
else if (Moisture_trigger >= 500 && Moisture_trigger < 599)
{
lcd.setCursor(0, 1);  //display on bottom line of LCD
lcd.print("60%");
}
else if (Moisture_trigger >= 600 && Moisture_trigger < 699)
{
lcd.setCursor(0, 1);  //display on bottom line of LCD
lcd.print("70%");
}
else if (Moisture_trigger >= 700 && Moisture_trigger < 799)
{
lcd.setCursor(0, 1);  //display on bottom line of LCD
lcd.print("80%");on
}
else if (Moisture_trigger >= 800 && Moisture_trigger < 899)
{
lcd.setCursor(0, 1);  //display on bottom line of LCD
lcd.print("90%");
}
else if (Moisture_trigger >= 900 && Moisture_trigger < 1023)
{
lcd.setCursor(0, 1);  //display on bottom line of LCD
lcd.print("100%");
}

//////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//This section selects what pump timing will be displayed on the LCD dependent on the value of the potentiometer//
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////

{if (pump_value 0 && pump_value < 99)
{
lcd.setCursor(0, 0);  //display on top line of LCD
lcd.print("2 seconds");  //display the value 
}
else if (pump_value >= 100 && pump_value < 199)
{
lcd.setCursor(0, 0);  //display on top line of LCD
lcd.print("4 seconds");  //display the value 
}
else if (pump_value >= 200 && pump_value < 299)
{
lcd.setCursor(0, 0);  //display on top line of LCD
lcd.print("6 seconds");  //display the value 
}
else if (pump_value >= 300 && pump_value < 399)
{
lcd.setCursor(0, 0);  //display on top line of LCD
lcd.print("8 seconds");  //display the value 
}
else if (pump_value >= 400 && pump_value < 499)
{
lcd.setCursor(0, 0);  //display on top line of LCD
lcd.print("10 seconds");  //display the value 
}
else if (pump_value >= 500 && pump_value < 599)
{
lcd.setCursor(0, 0);  //display on top line of LCD
lcd.print("12 seconds");  //display the value 
}
else if (pump_value >= 600 && pump_value < 699)
{
lcd.setCursor(0, 0);  //display on top line of LCD
lcd.print("14 seconds");  //display the value 
}
else if (pump_value >= 700 && pump_value < 799)
{
lcd.setCursor(0, 0);  //display on top line of LCD
lcd.print("16 seconds");  //display the value 
}
else if (pump_value >= 800 && pump_value < 899)
{
lcd.setCursor(0, 0);  //display on top line of LCD
lcd.print("18 seconds");  //display the value 
}
else if (pump_value >= 900 && pump_value < 1023)
{
lcd.setCursor(0, 0);  //display on top line of LCD
lcd.print("20 seconds");  //display the value 
}
  
}