Before my summer vacations, I decided to build a watering system for my decorative trees. The soil moisture is measured with a cheap IoT sensor and the water supply uses 12V airpumps pushing air in water bottles (this makes a safe separation between electric and water circuits), the electronic schema is as follows:

The 86Duino Educake computer monitors the humidity level once a day and will pump water if the level is too low, it sends data to Azure therefore I'll be able to see how things are going on...