The 26-year-old Johnson was 1-1 with a 4.03 ERA in 2007, his first full season in the majors. He was part of a surprisingly effective bullpen minus injured closer Jason Isringhausen in the Cardinals' World Series run in 2006.
The Cardinals said in a release Tuesday that the surgery will be performed by Dr. El Attrache, a colleague of Dr. Lewis Yocum.
Johnson was the Cardinals' top lefty reliever last year, with Randy Flores working in a secondary role. The team had not been in a rush for Johnson's return given the success of 38-year-old lefty Ron Villone, who was 1-0 with a 1.26 ERA in 13 games after making the team as a non-roster player.
The Cardinals diagnosed the injury as tendinitis in spring training.