In this tutorial, we are making an automatic plant watering/irrigation control circuit. This circuit is used for automatically water your plants, garden, etc. usually we don’t have time or we forget watering our plants and they eventually become weak or die.
In order to take care of them properly, we have to water our plants whenever the soil doesn’t have enough moisture. All your watering issues can be solved with this circuit it is easy to make and inexpensive as it is only using a few components.
Hardware Components
| S.no | Component | Value | Quantity |
|---|---|---|---|
| 1. | Input Supply DC | 9-12V | 1 |
| 2. | Probes | – | 2 |
| 3. | Transistor | 2N4401 | 2 |
| 4. | Resistor | 1KΩ, 50KRΩ | 1, 1 |
| 5. | Relays | 9-12V | 1 |
| 6. | Diode | 1N4007 | 1 |
Circuit Diagram
Working Explanation
The working of this circuit is simple. When the two probes will detect the absence of moisture content from the soil the resistance between them will decrease and they will let the voltage passed to the transistor. Due to which transistor Q1 will switch on and will provide a voltage at the base of the transistor Q2 hence the relay will be activated. You can connect any DC/AC pump or sprinkler system with the relay switch so that they can activate with it and your plants will be watered automatically on the preset value of dryness. A 50K variable resistor is used to adjust the circuit to switch on the relay on the desired level of dryness.
This circuit can be operated at 6, 9, or 12 volts DC. The relay should have the same voltage as the input voltage. For best results put the probes a few inches under the soil and make few feet distance between them or you can experiment with other procedures, observe and use the one that works best.
Applications and Uses
This circuit can automatically water your plants, garden, farms, irrigation areas, etc.
