First he learned the painter craft, after that studies followed in the studio of his father. Hellgrewe attended the schools for free and applied arts in Berlin. He became master pupil of Prof. Kuntschmann and cooperated later with him.

In the First World War Hellgrewe was heavily injured. After that he worked as a  free artist and restorer in Langensalza. In 1928 he became the substitute director of restorantion of the province of Saxony in Halle. After the Second World War Hellgrewe returned to Langensalza and was again active as a landscape painter, restorer and illustrator.