Tibbalds Planning and Urban Design will draw up a masterplan for phase one of the scheme, which proposes delivering about 1,000 homes to the north east of the site, plus a mixed-use town centre, commercial units, green space and landscaping, and a station linking into the nearby HS1 line.
Tibbalds said it would also create two separate design codes for the project. The first will be a strategic design code covering the whole garden town "with a strong focus on streets and public realm".
A second, more detailed design code would sit alongside the phase one masterplan, the firm added, "providing guidelines for developers and their design teams in relation to the town centre and other higher density areas".
The Otterpool Park site is located close to the M20 and near to both Ashford and the seaside town of Folkestone.
In addition to new homes, plans include employment, shops, schools, and medical centres, as well as extensive open space across a 770-hectare site that incorporates Westenhanger Castle.
It is being promoted by landowners Folkestone and Hythe District Council and Homes England and is part of the MHCLG's garden communities programme.
Katja Stille, a director at Tibbalds, said: “Otterpool Park will be a new garden town with culture and creativity at its core.
"Even though green space and open landscaping will be a central feature, this development will first and foremost need to function as a community, so it is essential to get the right infrastructure and facilities in place from the start.
“We are committed to ensuring sustainable, green, healthy principles are applied to all aspects of this new development, helping to maximise wellbeing and healthy living opportunities for the people who will live and work there.”
Sue Rowlands, Tibbalds director, added: “Creating strategic and more specific design codes will make sure that the quality of development continues over the next 30 years while allowing a flexible approach as the times change.
“At the same time, the masterplan itself will build on our work helping existing town centres throughout the country to remain attractive and economically vibrant places, such as Salisbury, Hertford, and Sutton Coldfield.”
Plans for the Otterpool Park garden town were submitted to the council in March 2019.