I've been programming esp32 connected with soil moisture sensors and solenoid valves to water each individual pot of plants according to its own readings, instead of having a centrally controlled irrigation system. Overkill, I know, but with a cost of 8-10usd per set up it is not expensive

Photos? If you have a blog post, it may be a good post for HN. (Bonus points if the plants survived :) .)