Among the many uses for seats, resting after a busy day is among the best. But people aren’t the only living things that need a rest. Sometimes house plants need to take a break from lazy or forgetful humans. This WikiSeat is a seat for plants.
The legs of the seat are from an apple tree that grows in the yard of the house where I live. This serves as the structure for the seat, and the magic happens in the electronics. There is an a Teensy board (derived from the Ardunio) that seres as the brain for this seat. A moisture sensor lets the brain know the current moisture content in the soil. Water conducts electricity, and this can be measured by the moisture sensor.
Over time, as the moisture evaporates from the soil, or is taken on by the plant, the soil becomes less conductive, and this can be measured. When the soil reaches a certain conductivity level (or level of dryness) the Teensy board turns on a peristaltic pump (from Adafruit Industries), which squeezes water through a tube. This pump can suck water from a lower level, forcing it upwards against gravity, and into the plant’s pot.
As with any electronics project, there is some really complicated stuff going on here. But at the same time, we live in an age where we truly are standing on the shoulders of giants, and much of the wisdom in the world is freely accessible online or at your local hackerspace. Most everything that Adafruit has comes with detailed instructions. Think of it as a larger, more advanced LEGO kit.
I’m still dialing in the code that determines at what point teh pump turns on, and how long it remains on for. Once I get some code that works reliably I will publish the link here.