Fanny Malcolm was born at Auckland, New Zealand, on 29 January 1852, the second of 13 children of Emilie Monson Wilton and her husband, Neill Malcolm, a barrister. When Fanny was six years old the family moved to Great Barrier Island, 56 miles north-east of Auckland, where Neill Malcolm began cattle farming at Rosalie Bay. It was here that Fanny spent her childhood and early adulthood. The property her father acquired was extremely run down and life there was hard and isolated.
The Malcolm children were educated by their mother in reading, writing and arithmetic. After lessons they were taken to the beach for recreational activity, which included drawing. Fanny's creative talents were first nurtured by drawing pictures in the sand. Emilie Malcolm recognised the talent in her children and gave it scope by providing proper art materials purchased from Auckland. Apart from these early sketching activities Fanny was given no training in art.
In 1874 Fanny married Alfred Joe Osborne, whose family farmed at Tryphena, about seven miles from Rosalie Bay; the ceremony was performed by Bishop William Cowie at Bishopscourt, Parnell, on 15 January. Both sets of parents had disapproved of the match. During the 1860s a bitter land dispute had developed between the Malcolms and other Great Barrier settlers, particularly the Osbornes, forcing the lovers to keep their affection a close secret. After their marriage Fanny and Alfred returned to the island to settle on the Osborne farm at Tryphena, where they raised 13 children: eight sons and five daughters. Fanny remained estranged from her mother for the rest of her life.
It is not possible to ascertain when Fanny Osborne began to produce her exquisite watercolours of the Great Barrier Island flora, for she did not usually date her paintings. Her husband was well educated and probably encouraged her in her choice of subject matter with his extensive knowledge of the local plant life. By the 1920s her work had become quite well known and she was selling sets of paintings and single works from her home at Tryphena. Her most creative period was probably after her children had grown and her family responsibilities had lessened.
From both scientific and artistic points of view, Fanny Osborne's paintings of the flowers of the indigenous trees, shrubs, vines and herbs of Great Barrier are exceptional and superbly crafted examples of botanical illustration. They are accurate in every detail, and yet simultaneously communicate the beauty and delicacy of the specimen. They also provide valuable historical documentation of the plant life of the island. One of the species depicted, Elytranthe adamsii (New Zealand mistletoe), is now extinct. The largest collection of her work is held by the botany department of the Auckland Institute and Museum.
All five of Fanny Osborne's daughters inherited her talents, the most active being Lilian, Ellen and Winifred. Lilian settled in England, and under her married name, Lilian Gibbard, became widely known for her flower studies. Towards the end of her life Fanny Osborne became crippled with arthritis. She died at Auckland, aged 82, on 12 March 1934. Alfred Osborne had died in 1920. Both are buried on Great Barrier Island.