This paper investigates some core aspects of Guy de La Brosse’s botanical work. In the first section, the focus is on the epistemological principles of La Brosse’s botany by analyzing the first and second book of the treatise De la nature, vertu et utilité des plantes. In the second section, the author discusses the role of Paracelsus’s chemistry in La Brosse’s work, with a particular attention to the third book of the De la nature. The final section deals with La (...) Brosse’s interest in the visualization of plants. Here, the author provides the transcription and first Italian translation of a short manuscript related to Abraham Bosse’s engravings for La Brosse’s unfinished book Icones posthumae. (shrink)