Known for his work as a bandleader and during the 1950s with Miles Davis, Garland helped popularize the block chord style of playing in jazz piano.

[4][5][6][7] Garland found success in 1955 when he joined the Miles Davis Quintet, featuring John Coltrane, Philly Joe Jones, and Paul Chambers.

Garland walked out of one of the sessions for Milestones; on the track "Sid's Ahead", Davis comped behind the saxophone solos in his absence.

Among the musicians the trio recorded with are Pepper Adams, Nat Adderley, Ray Barretto, Kenny Burrell, Eddie "Lockjaw" Davis, Jimmy Heath, Harold Land, Philly Joe Jones, Blue Mitchell, Ira Sullivan, and Leroy Vinnegar.

In the mid-to-late 1960s, Garland's career suffered when rock music caused a substantial drop in the popularity of jazz, and his record sales plunged.

In 1977, his Crossings album reunited him with Philly Joe Jones, with whom he also played club performances that same year.