She exhibited with the Royal Hibernian Academy (RHA) for the first time in 1900 with East wind effect and Roses.

She took a course at Norman Garstin's studio in Penzance, and stayed in North Wales in 1914, painting two Trearddur Bay scenes.

It appears that her portraits of children and dogs were popular based on her submitted works to the RHA, exhibiting without a break from 1900 to 1921.

The Hugh Lane Gallery holds her portrait of Lord Ashbourne, which demonstrates her painting style of loose brush strokes with an air of informality.

She spent two months in New York, staying with cousins at White Plains and then moved into a room neighbouring that of Yeats in Petitpas.

Her uncle strongly disproved of this living arrangement, so she left and returned to Ireland in January 1912, which upset Yeats greatly.

[1][2][3] Upon her return from New York, Marsh started holding classes at her studio at South Anne Street which Swanzy recalled were "well liked and always full", with Mrs Susan Yeats becoming a pupil.

Due to her early death, Marsh largely fell into obscurity until one of her works was included in the 1987 "Irish Women Artists from the Eighteenth Century to the Present Day" exhibition and publication from the National Gallery of Ireland.