The term chosen: Blue Grass

First used as an artistic term (not for music): 1719

Next used to describe “Poa” (actual “Blue” grass plant): 1794 (An historical, geographical, commercial, and philosophical …)

First reference to music from novel in 1974: Bill Monroe and his Blue Grass Boys: an illustrated …

After conducting this search I found that Blue Grass Music had not been literally mentioned until close to the mid 20th century and most previous references before that were about a genus of plant species called “Poa”. Blue Grass itself had a drastic rise in literary mention in the latter half of the 20th century.