Listen to Green Grassy Slopes of the Boyne / Orange Lily O / Derry's Walls / Battle of Garvagh online. Green Grassy Slopes of the Boyne / Orange Lily O / Derry's Walls / Battle of Garvagh is an English language song and is sung by The Diamond Accordion Band. Green Grassy Slopes of the Boyne / Orange Lily O / Derry's Walls / Battle of Garvagh, from the album Over 80 Orange Anthems, was released in the year 2014. The duration of the song is 3:06. Download English songs online from JioSaavn.