Founded in 1621, Oxford Botanic Garden is the UK's oldest botanical garden. The founder, Henry Danvers KG wanted a 'Physic Garden' to teach medical students about medicinal plants. Danvers leased the five acre site from Magdalen College, and the founding stone for the garden was laid by the University of Oxford's Vice Chancellor on July 25th, 1621.

ExperienceOxfordshire.org - Oxford Botanic Garden

obga.ox.ac.uk - A Brief History

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The first botanical garden was established back in Italy in 1545 when Venetian scholars and government officials implemented a botanical garden at the University of Padua, shortly after granting Francesco Bonafede's petition for the creation of a botanical garden back in 1543. Bonafede taught the 'lettura dei simplici,' or study of medicinal plants, and he recognized a need for the direct observation of nature in this branch of learning. 

Accordingly, Bonafede approached the rector of the universitas artistarum (which taught medical and botanical disciplines), requesting that a public garden be opened for the cultivation and study of medicinal plants and herbs – the so-called ‘semplici’ (medicamentum simplex). The request came before the Senate of the Venetian Republic, which in 1545 decreed that a suitable plot of land should be purchased. Padova’s Botanical Garden is the oldest university garden in the world, and it's retained its original location and layout over the...