RHS director-general Sue Biggs made the announcement at a press briefing this week. The summit will be live-streamed, and aimed at a different audience to the typical RHS member, with developers, planners and council officers all on the invitation list.
An RHS spokesperson said the main focus of the summit would be the ongoing drive to turn front driveways and gardens green again, while still retaining parking spaces for cars.
While the re-greening of front gardens will reduce flooding, it also holds obvious benefits for wildlife and human "health and happiness" which is the RHS's key theme this year.
Biggs said she was "delighted" to announce the summit which was a first for the RHS. "This is really important for our country," she said.
Landscape designers Tom Stuart-Smith and Christopher Bradley-Hole also outlined their plans for the new RHS Garden Bridgewater and the redesign at RHS Garden Wisley, respectively.
Stuart-Smith's design for Bridgewater will include a reconstruction of the historic Walled Garden, including a therapeutic and vegetable garden and a new lake. Christopher Bradley-Hole's design for Wisley will include a 160m tree avenue from the carpark to the garden through the new shop area.