Automatic Plant Watering System Circuit with Working

Nowadays, many people are facing a lot of problems watering the plants in the garden, especially when they are away from home. In such cases, watering plants become difficult as they are involved in other works. Without losing their time and efforts, many people can avail a better option in the form of an automatic plant watering system that helps watering the plants in the garden. This automatic plant watering system senses soil moisture, and then automatically switches the pump when the power is available. A proper use of the water to the plants is most important due to lack of rain and shortage of water. For this reason, we use this automatic plant watering system as it is very useful in all climatic conditions.

Automatic Plant Watering System Circuit

The circuit below shows a simple automatic plant watering system for automatically watering your gardens, plants, etc. Frequently, we cannot set the time for watering the plants due to which the soil of the plants becomes dry. So, for a proper care, we have to water the plants whenever the soil gets dry. This circuit contains two probes, which will sense the moisture of the soil and switch on the relay at the specific value of dryness. You can connect any sprinkler system or pump with the relay to switch the circuit on automatically to water the plants.

This circuit uses two transistors that work as switches. If the probes do not sense the moisture in the soil, then the resistance between the two probes will increase due to which the transistor Q1 will switch on. If the transistor switches on, it will provide the required voltage at the base terminal of the transistor to make a switch on, then the relay will become activated.

The variable resistor 50k is used to adjust the circuit  to switch ON the relay on the required level of dryness. This circuit operates with 6,9, or 12 volts DC. Instead of the probes, you can use any steel nail, wire or similar material. For best performance, put the probes few inches under the soil and maintain some distance between them.

Automatic Plant Watering System’s Block Diagram

The power supply includes a step-down transformer that steps down the voltage to 12V AC. This AC voltage is converted into a DC using a bridge rectifier, and then regulates 5V using a voltage regulator.This voltage is used for the operation of the microcontroller.

The block diagram of this automatic plant watering system includes 3 main gears, namely a microcontroller, a motor-driver circuit and a sensor circuit. When the sensor circuit senses the soil condition, it compares it with the reference voltage 5v. This process is done by a 555 timer.

When the condition of the soil is < 5V, then the soil condition is considered as dry and immediately the 555 timer sends the logic signal 1 to the microcontroller. Then the  microcontroller turns on the motor driver circuit and reminds the motor to pump water to the plants. When the soil condition is >5V, the soil becomes wet. Then the 555 timer sends the logic signal 0 to the microcontroller; this turns off the motor driver circuit. Finally, the condition of the motor and soil are shown on the LCD display.

For better understanding of this automatic plant watering system, the project of an Automatic Irrigation System on Sensing Soil Moisture Content is explained below.

Automatic Irrigation System on Sensing Soil Moisture Content

The main goal of this project is to design an automatic irrigation system in the field of agriculture.

The required components are: 8051 series microcontroller, Op-Amp, Relay, water pump, Diodes, Voltage Regulator, Capacitors, Resistors, Led, Crystal, and Transistor.

The power supply consists of a step-down transformer, which steps down the voltage to 12VAC. By using a bridge rectifier, this AC is converted to DC, then it is regulated to 5V using a voltage regulator which is used for the operation of the microcontroller.

The proposed system comprises three main components, namely an 8051 microcontroller, comparator and relay. This project uses an 8051 microcontroller which is programmed with Keil software. When the arrangement of the sensor senses the moisture of the soil, then it sends the command to the microcontroller by using a comparator. Here, the comparator acts as an interface between the sensing arrangement and the microcontroller. The arrangement of the sensor is made by using two stiff metal rods, that are placed into the field at a distance. Once the microcontroller receives the signal it generates the output that drives a relay and reminds the motor to pump water to the plants. The status of the water pump and soil is displayed on the LCD, which is interfaced to the microcontroller.

Thus, this automatic plant-irrigation system depends on the output of the humidity sensors. Whenever there is a need of excess water in the desired fields, then it is impossible to use sensor technology. But, by using DTMF technology, we will be able to irrigate the desired field in desired quantity.

This is all about an automatic plant watering system with circuit and block diagrams. We hope that you might have got a better understanding about this concept. Furthermore, for any queries regarding this article or electronics projects, please approach us by commenting in the comment section below