A special edition recorded in front of an audience at Write on Kew, the Royal Botanical Garden's new literary festival. Adam Rutherford examines the science behind the global challenges and innovative solutions to preserving the essential biodiversity of the planet. From new perspectives on how plant populations can be made more resilient, to the remarkable genetic diversity of plants just being revealed by new analytical techniques, to coffee - and how one of our most prolific yet threatened commodities be protected from a changing climate . Do we need a radical new approach - are the large scale climate fixes offered by geoengineering the right solution? Adam Rutherford is joined by panellists: Kew's Director of Science, Kathy Willis; evolutionary botanist, Ilia Leitch, Kew's research leader in plant resources, Aaron Davis and author Oliver Morton. Producer: Adrian Washbourne.