Kohlhagen was a key artist in the South Australian female artists movement of the 1930s and 1940s. Her deco inspired printed works were South Australia’s response to the works of Thea Proctor and Margaret Preston in NSW. She studied at the South Australian School of Arts and then, in the 1920s, with South Australian Artist James Ashton, the father of Will Ashton and the man who is credited with teaching and encouraging Hans Heysen to paint. Kohlhagen travelled to London to further her studies at the Royal Drawing Society in 1926-7 and won gold and bronze medals for her work. Her contribution to Art in Australia was significant. She exhibited with, and was a founding member of, the NSW Contemporary Art Society which promoted contemporary works around Australia and was the first contemporary art movement to embrace female artistic endeavor. With Dorrit Black she also encouraged creative expression for females by founding Group 9.
Her work is represented in the National Gallery of Australia and the Art Gallery of South Australia.