I tried watering the field today after having ALL techs fully researched. I dragged a master builder over to the field. It says "He sees strange dead flowers here." Under "Action", it says "Watering field." only for a split second, and then it quickly changes to something else such as "Nothing" or "Fixing hut." I am perplexed! I have all techs fully researched. And yes the lagoon water is flowing too.