The quango has snapped up Rachel Gilmour, director of comms at the National Farmers' Union, as head of strategic comms.
Whitehall comms man Alex Ross has joined as head of media and events and National Trust assistant director of comms Kirstie Hills has joined as head of corporate comms.
The hires have been handled by director of comms Adrian Long, who was appointed in February.
Long said: 'The environmental stakes have got higher. Climate change and the need to protect those at risk from flooding is a major challenge we face.' He said a second challenge was 'helping business and industry go beyond just complying with regulation so that they become greener and better equipped to get through the economic downturn'.