Adam Frost's gardening for health – breathing clear

Having clean air to breathe is vital to our very existence, but pollution is a problem and many parts of the world, cities in particular, are choking. Is there a solution? Could gardening, plants and trees be the answer to solving this serious crisis? Adam Frost chats to Professor Jennifer Gabrys the Chair in Media, Culture and Environment at the University of Cambridge, about the role plants can play in addressing air pollution.