The 68,800m² city centre area is part of a wider £450 million masterplan designed by Glenn Howells Architects for developer Argent, between the city centre’s Centenary and Chamberlain Squares.
It will include a series of new streets and public squares around the area’s historic listed buildings.
Director at the Bath-based practice Peter Chmiel, director, Grant Associates said: "We are thrilled and delighted to be appointed as landscape architects for Paradise Circus. This is a high profile project right in the heart of Birmingham and the public realm is a vital part of it.
"Grant Associates looks forward to working with the team and will ensure that the public space creates the best possible setting for this development and its wider environment."
Managing partner at Argent David Partridge said: "All the entries were of the highest quality and clearly followed the brief to create a world class public realm that would complement the listed historical and contemporary new buildings."
Grant Associates won two MIPIM Awards this month at the international property trade fair. It won the Best Innovative Green Building category and the Special Jury Award for the new Singapore public park, Gardens by the Bay.
The wins came on top of four awards at last year’s Landscape Institute Awards. Two of them - Large Scale Public Development and The College of Fellows Award were also for Gardens by the Bay.