The RHS, national charity Groundwork and landscape designer, broadcaster and gardener Chris Beardshaw are to feature an Urban Oasis show garden at every RHS show this season, starting in Cardiff on 20 April.
Cardiff will close the RHS's first National Gardening Week and will be the first RHS partnership with Groundwork, supported by "a significant commercially confidential sum" from Marks & Spencer.
The project aims to celebrate both their initiatives to get local communities gardening and involve more people in transforming neighbourhoods to revive urban communities.
Urban Oasis will showcase some of the most challenging urban environments where gardening, community work and good-quality landscape design have brought people together and yielded social benefits. The Cardiff show garden will be recreated by volunteers at the charity's environmental centre in Merthyr Tydfil.
Beardshaw said: "The green space around us has a fundamental effect on our emotions and behaviour. In areas where these spaces are neglected and poorly designed, we see strong evidence of social unrest and it is easy to see why.
"Whatever the green need, there is a solution, and it doesn't have to mean high cost. The Urban Oasis gardens showcase design solutions that can make such a difference in people's lives."
RHS director general Sue Biggs added: "We are delighted to be teaming up with Groundwork to champion the benefits of gardening in urban communities.
"A recent RHS report shows how important community gardening is to society and how the regeneration of urban areas is to transforming lives and livelihoods all over the country."
Groundwork on the concept for its Urban Oasis show garden
"This will be at every RHS show bar Chelsea, coming together for a centrepiece at Hampton Court. The idea will be to replicate a Groundwork project nearby to the RHS show. Chris Beardshaw has consulted Groundwork landscape architects to understand the challenges and how their designs help communities get involved and show the benefits of quality green space."
Gary Campbell, Groundwork representative.