At the age of twelve, after attending the local elementary school, he became a choirboy at the local monastery where he continued his education and received his first drawing lessons. When the monastery closed, the fathers recommended that he become a church painter. Johann Franz Schefold (1750-1828), a lawyer whose father was a church painter, acted as a sort of patron to Pflug, allowing him access to his library and gallery. In 1806, he went to the Academy of Fine Arts Munich where he studied under Johann Christian von Mannlich, whose instruction consisted largely of having him make copies of the Dutch Masters. At the outbreak of the Tyrolean Rebellion, he returned to Biberach where he passed an art examination and became a teacher at the newly created Biberach Gymnasium, a post he held until 1856.