This dissertation situates eighteenth-century botany within the contexts of contemporary commercial culture and international networks of knowledge formation. I assess the connections between scholars, merchants and consumers in London and Paris between c. 1760 and c. 1815. I ask how individuals who made a commercial profit from selling science understood and related to the notion of a community of scientific practitioners. My aim is to expose the diversity of socio-intellectual configurations that existed in the late eighteenth century. I focus on the histories of two plant nurseries, one based in London and the other in Paris. Their commercial successes rested on their proprietors’ abilities both to serve the growing consumer demand for plants and to actively participate in the international scientific community. The first three chapters address how each participated in scientific and commercial networks, examining which groups composed these networks, the types of social relationships they formed, and how knowledge circulated between them. I highlight the role played by ‘gardener-botanists’ who acted as intermediaries between each of these groups. The final two chapters focus on the people who purchased and exchanged plants. I assess who comprised the ‘public’ that collected specimens and studied botany, and I examine how gardens in London and Paris formed part of an expanding space for science. I emphasise in particular the significance of the culture of connoisseurship to the history of botany, and discuss the range of different publics who collected plants and studied their science. My research is concerned with the interplay between knowledge, commerce and culture. Drawing from the notion that scientific knowledge is always socially and culturally situated, I aim to connect the history of the plant trade to the development of the science of botany, and to place these within a wider cultural context.