Blue Grass is a city in Scott County, Iowa, United States. A small portion of the city extends into neighboring Muscatine County. The population was 1,169 at the 2000 census. Most of Blue Grass is part of the Davenport–Moline–Rock Island, IA-IL Metropolitan Statistical Area, but the Muscatine County portion of the city is considered part of the Muscatine Micropolitan Statistical Area.