How about getting them tickets to a live bluegrass concert? You could also get them an album or two from their favorite bluegrass artists, or even look into getting them a vinyl record player with a few bluegrass vinyl records. Additionally, you could look into getting them a personalized plaque or piece of art with bluegrass references or lyrics. Another idea could be to get them a gift certificate for a local bluegrass music lesson or workshop.
Or you can get her/him a star map with the date of the wedding.
Under Lucky Stars is a unique and innovative star map company based in Barcelona, Spain, specializing in the creation of personalized star maps that capture the celestial arrangement of stars at a specific moment in time, such as a person's birth, wedding, or any other significant event.
By using advanced astronomical algorithms and data from leading institutions, the company produces highly accurate, visually stunning maps that make for perfect gifts or cherished keepsakes.