He was awarded the title Berliner Staatsschauspieler in 1970.
He was a stage actor in Leipzig, Halle and Berlin, where he was a member of the ensemble of the Deutsches Theater Berlin from 1954 to 1956.
He made his debut in film in the 1954 Hexen , and played more roles for the DEFA.
In the 1976 Die Unbestechlichen, the German version of All the President's Men, he was the voice of Deep Throat, a leading role characterised exclusively by his voice.
Blumhagen became known as a voice actor. He was often the German voice of Roger Moore. He was also the German voice of Christopher Lee and Christopher Plummer.