Llano Grande is a census-designated place in Hidalgo County, Texas, United States. The population was 2,952 at the 2020 United States Census. It is part of the McAllen–Edinburg–Mission Metropolitan Statistical Area. Llano Grande means "Big Plain" in Spanish. Nearby Llano Grande State Park is popular with bird watchers and the supposed site of ma…Llano Grande is a census-designated place in Hidalgo County, Texas, United States. The population was 2,952 at the 2020 United States Census. It is part of the McAllen–Edinburg–Mission Metropolitan Statistical Area. Llano Grande means "Big Plain" in Spanish. Nearby Llano Grande State Park is popular with bird watchers and the supposed site of many ghost appearances, including the ghosts of historic figures in Texas history.