Author here. This started as a 2 m² vegetable bed and got out of hand: 8 soil probes, a weather station, a camera, and a Rain Bird valve that I control through an old Android phone tapping its own app.

The part I found interesting: a fixed rules engine for watering kept being wrong in ways that needed context (forecast, last week's response, what the leaves look like). So an agent now runs every morning, reads the full history (4M readings, 62 MB in Iceberg), changes watering within hard limits, and logs what it expects to happen so it can check itself the next day.

Disclosure: the data side runs on LakehouseBox, which I'm building. The code is at github.com/jatorre/garden-lake. Happy to answer anything, including "why not Home Assistant."