Combining the D1 Mini and Blynk to create a wireless Soil Moisture Sensor…
This small portable sensor can be used to alert you to the moisture condition of your plants. In the future it can be combined with a water pump to create a fully automatic garden system.
To begin you will need to download and 3D-print the 3 separate parts available via thingiverse.
You will need the following components:
WeMos D1 Mini
3.7V 14500 Li-ion Battery
Capacitive Soil Moisture Sensor
D1 Mini Battery Shield
WS2812 RGB LED
1 x AA Battery Holder
Connect everything together using the following schematic:
The shield can be connected directly to the D1 mini. The breadboard is used above for reference only and components should be soldered and crimped together in order to facilitate positioning inside the printed housing.
Remember to connect the RST pin to D0 in order to enable sleep mode.
The final assembled device should look similar to the image below:
Download the Blynk App to your smart phone/device and create a new project based on the following:
Upload the sketch to the D1 Mini using the Arduino IDE. Edit the sketch to include reference to your WIFI SSD and password as well as your unique Blynk authentication token.
Insert and charge the battery and watch the data roll in…
Use the sliders in the app to adjust the threshold at which the dry/wet alerts are activated. The sketch can be further customised if your sensor needs it as well as for things like the length of time to sleep.