Caroline Barbara Newdigate was the eldest daughter of William Henry Newdigate* and his wife Caroline, born Duthie, and was born on her parents' farm "Buccleugh". She shared her father's interest in moths and collected various natural history specimens in the Plettenberg Bay area. These included excellent living specimens of several rare species of orchids, which she sent to Harry Bolus*, who acknowledged her assistance in the preface to Volume 2 of his Icones Orchidearum... (1911). At this time she was already living at Forest Hall, the family's estate in the Tsitsikama Forest. She also sent dried plants to P. MacOwan* at the Government Herbarium in Cape Town. With some of her sisters she collected moths, butterflies and sea shells. The moths were sold to museums overseas and the money was used to build a small chapel on the estate. In 1896 she donated the insect species Horia hottentota to the South African Museum in Cape Town.
Caroline's plant specimens are housed in the Bolus Herbarium, University of Cape Town, and the Compton Herbarium of the National Botanical Institute, Cape Town. The Blind orchid, Pterygodium newdigatae, was named after her by Bolus. She was not married and during her later years resided at Forest Hall.