While the phrase “My Grass Is Blue” has been around for decades, it was made famous by the cover of Lynyrd Skynyrd’s 1977 album Street Survivors. Skynyrd bassist Leon Wilkeson was wearing a t-shirt that read “My Grass Is Blue” on the cover.
Find the original My Grass Is Blue T-Shirt here
The album, which featured the band members standing in flames, gained unfortunate massive notoriety because the band’s plane crashed in Mississippi just three days after the album’s release, killing three members of the band, a road manager and two crew members. In fact, the cover of later pressings of the album had to be altered to remove the flames.
The phrase “My Grass is Blue” is really just an idiom, meaning the wearer is a fan of bluegrass music.
“Grass” was also popular slang for marijuana in the 1960s, so the phrase had undertones of hippie & weed culture. Particularly in the 1960s and 1970s, a surge on popularity of folk music boom lead by Bob Dylan also helped give rise to the popularity of bluegrass music.
Bluegrass music itself, with roots in Appalachia, was named for the grass that was unique to Kentucky. Early settlers noticed the grass had a blue hue in the sunlight. The father of bluegrass, Bill Monroe, popularized what would become the genre while touring as Bill Monroe and the Blue Grass Boys.
So for the last several decades, the phrase “My Grass is Blue” has ben a popular way to say you love bluegrass.
Dolly Parton even released her own Grammy-winning bluegrass album in 1999, titled “The Grass Is Blue”.