In this tutorial, we are going to make a Plant watering watcher or Dry soil detector. Not all of us remember watering the plants and as we all are aware of the fact that if they are not watered enough they die. In order to avoid that you need to check your plants regularly but we often forget to water the plants in our homes or offices because of the load of work. The plants located indoors need more care as compared to the plants outside. This is a great circuit to solve all your problems.
This device will remind you to water your plant whenever it gets dry or requires water. It will give a beep and the LED will glow up when the two probes of this circuit will not detect any moisture in the soil of the plant.
Hardware Components
Dry Soil Detector Circuit
| S.no | Component | Value | Quantity |
|---|---|---|---|
| 1. | Resistor | 100Ω | 1 |
| 2. | Variable Resistor | 300K | 1 |
| 3. | LED | – | 1 |
| 4. | Transistor | 2N2222 | 1 |
| 5. | Buzzer | – | 1 |
| 6. | Probes | – | 1 |
2N2222 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of 2N2222
Dry Soil Detector Circuit
Working Explanation
This circuit can be operated at 3.6 volts. Two probes are used to detect the presence of moisture in the soil. When the soil becomes dry the probes will detect it and it will let the current pass to the transistor which will activate the LED and the buzzer. A variable resistor is used to set the desired level of soil dryness to activate the LED and the buzzer.
To adjust the circuit, insert the probes when the soil is moist and adjust the variable resistor slightly until the LED and buzzer go off. Now take out one probe from the soil, If the buzzer and the LED activate it shows that the circuit has been adjusted and is ready to be used.
Applications and Uses
This circuit can be used as an alarm for your plants at home, offices, greenhouses, etc. With some modifications, it can be used for irrigation as well.
