Ludwick had been out with a strained hamstring.
The Cardinals on Friday also placed shortstop Khalil Greene on the 15-day disabled list because of social anxiety disorder. The move was retroactive to Thursday.
Ludwick was batting .274 with eight home runs and 26 RBIs at the time of his injury on May 12.
He was to be in uniform for the Cardinals' series opener in San Francisco on Friday.