Guardian: People around the world need to embrace a “new deal” to recognise the economic, health and environmental benefits of plants, according to the outgoing director of Kew Gardens in London. A fifth of the planet’s plant species are in danger of extinction within the next century, said Prof Stephen Hopper in an exclusive interview with the Guardian, and governments around the world needed to make firm plans to reverse the decline. “We’re at a crossroads in many ways, we now have half the remaining wild…