[1] Campbell attributed her interest in botany to walks that she had taken with her father as a child;[2] she was also influenced by a family friend, botanist Helen Kirkland Dalrymple.

[1][3] After graduating Otago Girls' High School, Campbell took a two-year course at Dunedin Teachers' Training College.

[1][2] Her thesis, "The embryo and stelar development of Histiopteris incisa", was published in Transactions of the Royal Society of New Zealand in 1936.

[4] Upon graduation, Campbell taught at Waitaki Girls' High School in Oamaru for a year and then became an assistant botany lecturer at Victoria University of Wellington.

[1][6] She lectured on plant morphology and anatomy and led research field trips to Himatangi Beach, Kapiti Island, and Tongariro National Park.

[2] She also conducted international field work, such as trips to the University of Cambridge, Singapore, India and Nepal; Australia; Malaysia; Japan; the United States; and Canada.

[2] In 1978 Campbell published her finding that the Equisetum arvense (field horsetail) growing on nursery land in Palmerston North was an invasive species, after years of others thinking that it was an ornamental plant.

[8] She also wrote internationally acclaimed papers on the "mycorrhizal associations of New Zealand's achlorophyllous mycotrophic terrestrial orchids, Gastrodia cunninghamii, G. aff.

[1] Her most prominent awards included being appointed a Fellow of the Royal New Zealand Institute of Horticulture (1976), receiving the Massey Medal from Massey University (1992), and her appointment as a Dame Companion of the New Zealand Order of Merit, for services to science, in the 1997 New Year Honours.