One thing about successful plant growing it to keep proper moisture level of soil. This is even more important when plant is pot where it has no way reach water source. To avoid drying out or over-watering – a simple electronics can help. Of course this can be achieved with simple 555 timer based buzzer sensor. But why bother if there is a spare Raspberry Pi. Jeremy Blythe shared his build where his raspberry Pi successfully monitors his plants.
He used soil moisture sensor brick which gives analog signal. Raspberry Pi cannot read analog, so there is an external ADC (MCP3008) used which interfaces via SPI. Jeremy put external circuit on a sticky breadboard which stuck nicely to plexiglass. On top of RasPi he placed Adafruit RGB negative 16×2 LCD with keypad. As all good things in Raspberry Pi this one is also controlled with help of Python script. With his project he also wanted to show various ways of displaying sensor information. So he covered LCD, console, and even remote with ControlMyPi service.