Born into a middle class family, Miller's mother Sybilla encouraged her to learn about art. Miller studied her craft in Halifax first at a school run by Eliza Thresher on Salter Street, and later under the tutelage of a visiting British painter named L'Estrange. She also studied with W.H. Jones, a Bostonian who taught at
Dalhousie College. In 1830, she began offering drawing classes to female students which gave her some financial independence. By 1833, Morris began to produce watercolour drawings of local flora with her own descriptions. Soon after, Nova Scotia's Secretary of Agriculture and botanist,
Titus Smith Jr., asked Miller to paint a series of canvases depicting local wildflowers. He brought her specimens, which she quickly had to immortalize, before the plants deteriorated. It was issued in 1840 by a London bookseller and local publisher, with the financial support of the province's
lieutenant-governor Sir Colin Campbell. A set of these prints was given to Queen Victoria, which bolstered Miller's reputation significantly. In 1867, the first series was reissued with a new title,
Wild Flowers of British North America. With her four catalogs, Miller was able to document 22 native plants, at a time when there was an increasing interest in natural history. In 1867, a copy of her botanical paintings were exhibited at the
Paris Exposition. Miller's works are part of the permanent collection at the
Art Gallery of Nova Scotia, Atlantic Canada's largest art museum. Other paintings and lithographs are owned by The Nova Scotia Museum of Natural History, also located in Halifax.
Ottawa's
National Gallery of Canada has some of her lithographs as well, belonging to the 1840 and 1853 series. Also a writer, Miller published a volume of poetry,
Metrical Musings, with her sister Catherine in 1856. == Personal life ==