With her family’s encouragement, Buchanan attended Bennett College, where she earned a degree in medical technology with the aim of attending medical school. Following advanced degrees in parasitology and public health at Columbia University, she held positions as a medical technician and public health educator. While she commuted to work in the Bronx and New Jersey, she observed myriad remnants of derelict buildings that evoked the tenant houses of her youth in the South.

In 1971, Buchanan changed course: she enrolled at the Art Students League. There she studied under Noman Lewis and found mentorship with other contemporary artists such as Romare Bearden. In 1977, she moved to Macon, Georgia, to pursue art full time, and she credits her early medical studies for inspiring her desire to investigate and seek information from a variety of sources, and then piece together answers. As such, she experimented with diverse media and approaches, ranging from land art to photography to drawing, to produce a dynamic oeuvre that offers a connection to place and reckons with histories that shaped communities in the South.

Buchanan earned a BA from Bennett College, and an MS and MPH from Columbia University. She is the recipient of awards such as the John Simmon Guggenheim Memorial Foundation Fellowship (1980); the National Endowment for the Arts Fellowship (1994); and the Anonymous Was A Woman Award (2002). The Studio Museum has presented her work in exhibitions including Ritual and Myth: A Survey of African American Art (1982); The Decade Show: Frameworks of Identity in the 1980s (1990); and When the Stars Begin to Fall: Imagination and the American South (2014).