Blom began his acting career in 1893 in Kolding, and was employed as a company actor for the Folketeatret from 1907 to 1910.

Blom was a prolific filmmaker and during the golden age of Danish silent films, 1910 to 1914, he directed 78 movies.

Blom refined this genre during the following years, and this became the most profitable trademark for Nordisk company films.

Harald Engberg of the Politiken newspaper later wrote in an obituary that Blom "knew that he wasn't some directorial genius, but he proved that he was the cleverest and most tasteful scene creator of his day.

After they divorced, he married a second time in 1917 to the actress Johanne Fritz-Petersen, the widow of Theater Director Fritz Petersen.