She showed early talent for painting and writing, and took lessons with various painters, including Christian Krohg.

Her first story for children was "Afbrudt 17. mai", published in the magazine Illustreret Tidende for Børn.

[2] In 1895 she published her first book for adults, the short story collection Som kvinder er, about the poor circumstances for unmarried women, and in 1896 the puberty novel Ungt sind.

[2] In an obituary from 1913, Sigrid Undset emphasized Zwilgmeyer's two faces, the nice children's writer and the more bitter critic of society.

[2] What Happened to Inger Johanne was a compilation of short stories translated into English by American children's author Emilie Poulsson.

Accompanied with illustrations by Florence Liley Young, the English language version was published in Boston in 1919.