This project consists of creating an automatic watering system for plants, which triggers a water supply only in case of need. Suitable for a single plant or a small plantation, this system can be replicated at different scales. It will allow you to maintain your plants in your absence, or to manage the growth of species particularly sensitive to moisture by setting fine adjustments. This automatic watering device will provide an opportunity to study the use of an analog signal from a sensor to activate a fairly powerful actuator (here an electric pump) using a relay.
Located close to the plant or plants to be monitored, the installation monitors the state of drought of the earth using a dedicated sensor, characterizing the resistance of the earth between two electrodes. This information is then used to activate, if necessary, a 5V pump, driven by a Micro:bit board to supply plants with water.
To make the mounting, you can connect
For the soil moisture sensor:
For Relay :
For the water pump:
Here is the Makecode program for the automatic watering system: