Born in Vernon, Texas, his brothers Charlie and Clois "Cub" and his sister Norma also became noted professional musicians. Teagarden's father was an amateur brass band trumpeter and started young Jack on baritone horn; by age ten he had switched to trombone. He first heard jazz music played by the Louisiana Five and decided to play in the new style. Teagarden's trombone style was largely self-taught, and he developed many unusual alternative positions and novel special effects on the instrument.