This dissertation is about the early history of the concept of nature (φύσις or φυή/φυά) in Greek poetry and philosophy, and the significance of certain metaphors for that history, especially ones relating to plants (φυτά). The derivation of φύσις and φυή/φυά from the verb φύω/φύομαι (“grow,” but also “come to be”), which is likewise the source of φυτόν (“plant”), continues to nourish arguments about the historical role of the vegetal paradigm in the development of the Greek concept of nature. The recent and widespread renewal of interest in nature and vegetation, in early Greek literature and innumerable other contexts, warrants a fresh assessment of the evidence, both with regard to the precise concepts of nature operating in the different corpora, and with regard to the precise significance of the vegetal metaphors. This dissertation focuses on two corpora, belonging to the fifth-century poets Pindar and Empedocles. In an era of conceptual revolutions and intense renewal and experimentation with metaphors in poetry and other discourse, both of these poets became famous for their metaphors as well as for their concepts of nature (for which Pindar uses both φύσις and φυά, Empedocles only φύσις). Novel analyses of their conceptualization of nature in Chapters 1 and 3 are paired with assessments in Chapters 2 and 4 of the significance of their plant metaphors, such as Pindar’s “fruit of the mind” and Empedocles’ elemental “roots.” Although it is commonly asserted that their vegetal imagery implies a concept of a universal Nature, it has been shown that their (and their contemporaries’) concepts of φύσις and φυά were limited to concrete individuals or groups; moreover, this dissertation argues, against the scholarly consensus, that both authors consistently use φύσις (and Pindar also φυά) to designate the “nature” or hypostatized collection of innate characteristics of an individual or group. One of the general tasks therefore of this dissertation is to show how vegetal metaphors bear on the explicit conceptualization of φύσις or φυά while also showing how certain metaphors prefigure the concept’s later history. Drawing on work in historical poetics, historical semantics, the history of concepts, and the history and theory of metaphors, this dissertation examines how the emerging concept of nature entered into original and powerful relationships with vegetal metaphors in the poetry of Pindar and Empedocles.