Lyric discussion by gradx 

Cover art for A Book Unfinished lyrics by Iron & Wine

a story (book unfinished) about a beautiful, materialistic girl (raven hair), who leaves a guy because he filled her greed and ego (presented a mare, leaving him to tend the land). He becomes depressed and gives up on everything (Drier quarter when it met his lonely hands). He no longer has to apologize for her (No more guilty left to pardon) and is left with his own misery (evil).

then it starts to talk about someone else, someone who sought love and innocence (virgin), not beauty (Blind man), and happiness was restored (From the farmland proven fertile since the rain returned again). However, since this guy has given up (But you returned the book unfinished to your friend around the bend), he'll never know of better. there is also the noticeable transition at the end from a nuisance (weeds) to something that helps nurture (sparrow).

i think the garden is a metaphor for happiness. turns out this wasn't my situation at all but i enjoyed trying to interpret it.