Timothy Walker is a British botanist. He has been the Horti Praefectus (Director) of the University of Oxford Botanic Garden and Harcourt Arboretum.
From 1977–1980, Walker studied for a BA degree in Botany at University College, Oxford. From 1980–82, he was a trainee gardener at the Oxford Botanic Garden. He studied for a National Certificate in Horticulture at Askham Bryan College in North Yorkshire during 1982–83. Then during 1983–84 he was a trainee gardener at the Savill Garden in Windsor Great Park. He was a diploma student at Kew Gardens during 1984–85. From 1986–88 he was General Foreman at the Oxford Botanic Garden and in 1988 he became Horti Praefectus of the Garden. He also holds a lectureship in Plant Conservation at Somerville College, Oxford and is a Lecturer in Biological Sciences at the Department of Plant Sciences, University of Oxford. He has won four gold medals at the Chelsea Flower Show in London.
In June 2011, Walker presented Botany — A Blooming History, a series of three television programmes broadcast on BBC Four, covering the history of botany.