Trichome October 14, 2016 thcscience_admin The tower of Magdalen College seen from the University of Oxford Botanic Garden. Established in 1621 as a physic garden growing plants for medicinal research, it contains over 8,000 different plant species. Credit: Harshil Shah The tower of Magdalen College seen from the University of Oxford Botanic Garden. Established in 1621 as a physic garden growing plants for medicinal research, it contains over 8,000 different plant species.