Is it possible to grow sustainable food for everyone? Can it be produced in a way that makes financial sense for farmers? Are we too idealistic or not enough? Do urban food "thinkers" really get the practical realities? How can technology move things forward?We speak to Guy Singh-Watson, founder and co-owner of Riverford, one of the UK's biggest organic veg box schemes, and a pioneer in sustainable food. First, Jez and Nina kick-off with their thoughts on the Oxford Real Farming Conference - veganism, plastic and Michael Gove.