Well, I guess you are right — sometimes you’ve just got to trust the algorithm 🙂 To be fair, the algorithm is a pretty simple, heuristics-based one. For example — it uses the average temperature, which in your case is pretty low. But your highest temperature during the day may be quite high, and you would be wondering why it doesn’t decide to water during the day. Well, all I can say is it’s after all not a real gardner, so it can’t make very intelligent decisions. But hopefully the ups and downs will be averaged out, so that it does the right thing over time.