Arduino project · Water and plants · Medium
Plant Monitor: Soil, Light and Temperature
Three sensors tell you how your plant is doing. A red LED warns when the soil is dry.
What you will learn
- How to monitor a plant with several sensors
- How to use one display for three readings
- How farmers use sensors
How it works
The LCD shows soil moisture, light and temperature. The red LED lights below 30 percent soil moisture.
Try this next
- Start a pump when dry.
- Send the readings to the cloud.
- Add a night light.
The simulator program and explanation on this page are original. The idea follows a classic Arduino project that students have built for years.
Parts: sensors and actuators (tap to show or hide)
Try the inputs (virtual sensors)
Pins (you can change them)
| Part | Arduino pin (change it here) | How to wire it |
|---|
Every wire, one by one
Red rail = 5 V from the Arduino 5V pin. Black rail = GND. The coloured wires carry signals. Match the wire colours on the drawing to this list.
| # | Colour | From (part and leg) | To |
|---|
Steps run from top to bottom, then start again. While the simulation runs, the active step is highlighted in green.
Quantities come from the parts you added. The store links open a search for that item on Robu.in, Amazon.in and ThinkRobotics, so you always see what is in stock today. Check the model, voltage and price before you order.
| # | Item | Qty | Search term | Buy / compare |
|---|
The PDF has the circuit sketch, pin table, every wire, sequence, full code, the parts list with store links, do’s and don’ts for each part, and the safety notes. The project file lets you come back and keep editing.
In the real world
A plant that tells you when it is thirsty
Lower the soil moisture in the simulator. The soil dries and the plant starts to droop.
Tip: use the gold tab at the bottom of the circuit drawing to pull the real-world view up over the Arduino board. Your parts stay visible above it, so you can press a button and watch the real scene react.
- Soil moisture sensor = how wet the soil is