Katharine Saunders (born Wheelwright) was the daughter of Canon Charles A. Wheelwright and his wife Anna, and grew up in Northamptonshire. She showed an early aptitude for painting and music, and was much involved in her father's parish activities. However, at the age of 19 she broke away from home and went to live on the European continent to study languages and drawing, encouraged by her brother Horatio who was becoming a well-known naturalist, traveller and writer. In June 1851 she married James Renault Saunders (1818-1892) in Brussels and they settled near London. James was offered a post as manager of the Natal Company, a syndicate of London and Cape businessmen who had acquired extensive properties in Natal, and in October 1854 he and Katherine arrived in Port Natal (now Durban). They settled on a sugar estate at Tongaat, north of Durban., which James Saunders bought in 1860.
Katherine's interest in the Natal flora was stimulated by M.J. McKen*, who managed their estate until 1860, and she started painting flowers soon after her arrival. Over the years her home became a convenient meeting place for local plant collectors. The botanical illustrator Miss Marianne North* stayed there in May 1883 when visiting Natal. During 1881-1882 Katherine visited England and continental Europe, taking with her a large collection of plants, some her own, others collected by various other persons. She also had more than 70 sketches with her, mainly of orchids, which were her main interest. The high quality of her work was recognised by J.D. Hooker*, director of Kew Gardens, with the result that she became one of his important collectors and correspondents in South Africa. She also met W.T. Thiselton-Dyer*, Hooker's eventual successor, who acknowledged her contribution of interesting plants from Natal, Zululand, and the Lebombo Mountains in the preface to Volume 6 (1897)of the Flora Capensis. She also corresponded with W.H. Harvey* in Dublin, and later H. Bolus* in Cape Town. A woman of undoubted ability and perseverance, she was keen to have plants named after herself and her son. As a result she was commemorated in the names of about twelve plant species (including Habenaria saundersiae, Drimiopsis saundersiae, Sisyranthus saundersiae and Haemanthus katharinae), while three were named after her eldest son Charles J.R. Saunders*, and one after his wife Maud.
Katherine undertook a journey to Swaziland and the eastern Transvaal in 1887, another to Heidelberg in 1889, visited England again in 1890, and visited her daughter in Johannesburg in 1892 and 1897. She continued painting wild flowers during her travels. Plants were often sent to her by other residents of Natal, particularly by her son Charles, and she continued sending specimens to Kew until the year of her death. In total 119 species that she sent to Kew were included in the Flora Capensis. In 1889 she presented some of her paintings to the Natal Society, which placed them in their museum (later the Natal Museum, Pietermaritzburg). The majority remain in the library of the Tongaat Group and 106 of these were later published as Flower paintings of Katherine Saunders (Tongaat, 1979) to mark the Group's diamond jubilee. In all some 700 of her floral paintings survive. Critics of her work (Rourke & Manning, 1992) have pointed out that she sometimes positioned plants unnaturally to show, for example, a top view of the flower and a side view of the rest of the plant. After her husband's death she joined the anti-vivisectionist movement and developed an interest in genealogy and spiritualism.