As a portrait artist she specialised in portraiture painting, especially watercolours, but also created works in pencil, pastels and oil.[2][3] Her portraits would be found in the National Gallery of Australia, Parliament House in Perth, and at the Perth City Council.[2] Her works include J.W. Johnson Esq., The Tartan Scarf, The Debutante and the Resting Model.[4] Her portraits of Prime Minister John Curtin and Perth Art Gallery curator George Pitt Morison are found in the Art Gallery of Western Australia, while James Mitchell's portrait was in the Treasurer Building and John Kirwan in Parliament House.[5] Johnson also exhibited her portrait of Pitt-Morrison for the Archibald Prize.[6][7] Her other exhibits for the prize included General Gordon Bennett.[8]
She was a member of the West Australian Society of Arts,[1] and taught painting and art at the Busselton Technical School.[6]
In 1934, her model for a portrait plaque of Edith Cowan was chosen from several local Western Australian entries to be the choice for a memorial work on a clock tower in Kings Park, Perth.[1] The Cowan bust was in high relief above a wreath of gum leaves and nuts and was cast in bronze, above a bronze inscription on the eastern face of the clock tower.[1]
