杜甫 wrote it around 761, while living in his thatched cottage in Chengdu:
好雨知时节，
当春乃发生。
随风潜入夜，
润物细无声。 'The good rain knows its season and comes when spring arrives. It slips into the night on the wind and moistens everything, fine and silent.' It ends at dawn with the city's flowers heavy with rain:
花重锦官城.
