Botanic gardens and arboreta are amongst our most loved public spaces. There are over 2500 botanic gardens and arboreta across the world visited by an estimated half a billion people each year (see: https://www.bgci.org/about/botanic-gardens-and-plant-conservation/), providing in many cases a much-needed connection to nature and plants for people living in urban environments. Many of us will recognise the joy of discovering a green public space amongst the urban sprawl of a city, or losing oneself in the floral diversity of a botanic garden. The human need to connect with nature was made evermore apparent during the recent Covid-19 pandemic, which boosted awareness of the value of plants and their positive effect on human well-being (Burke et al., 2022). Green spaces, including parks and botanic gardens, became sanctuaries for people's physical and mental health, so much so that many research groups around the world are seeking to understand the health and well-being benefits of being in green spaces and the mechanisms that underlie them. In this context, there is irony in the fact that the oldest botanic gardens in the world were established as medicinal, ‘physic’ gardens for teaching students the plants that supplied their medicines.
