I had no recollection of this poem at all. Really good one though. I don't know if this is correct, but I interpret tomeku as implying that the subject has *come to* somewhere (in search of something), which means that I see the structure here as more like: 3 lines of flower-and-water wandering reverie, then 1 line to bring us back to earth, and the final line as a realization that we are standing on a cold, silent mountain from which Spring is already gone.

Nice one on "hither and yon" for /manimani/, that's a thought-provoking take. --Matt