Ellen Ann Willmott, although known primarily as a horticulturist, was also an amateur musician and the owner of an important library. As well as containing books on botanical subjects, this library was particularly strong in its early modern musical contents, both manuscript and printed. This article examines the early modern music in Ellen Willmott’s library (which featured composers ranging roughly from Thomas Tallis to Henry Purcell), her collecting habits, and her methods of acquisition. It also evaluates what happened to her library after her death, including the circumstances of its dispersal by auction in 1935, charting the disposal of the more significant items to their various winning bidders. In so doing, it offers a window onto the economics of the music trade — a trade driven by an item’s condition and completeness, and stimulated by the early music revival.