Land Use Consultants, which is masterminding the £1.8m restoration of the 70ha grounds around ruined Lowther Castle, Cumbria, advertised recently for the post.
Principal Dominic Cole said: "We want to get the person on board during the design rather than imposing a garden on whoever is going to be running it.
"We are looking for someone with the sort of skills of Michael Walker at Trentham Gardens, who runs garden events and is personable. There will be a strong ambassadorial role in this job, which is particularly important given that this is publicly funded. For this reason we are calling the post 'head gardener plus'."
North West Regional Development Agency and the EU are funding the £9m costs of the restoration of the 17th-century gardens and castle walls ad turrets.
Cole said: "The castle fell into disarray in the 1950s and needs stabilising. Lawns were used for chickens and the commercial planting of rows of Christmas trees.
"But there's still a huge amount that can be seen when you walk through the woods including banking, walls and the shape of the garden with its trees and avenues."
Cole's company won the job in a competitive tender last year (HW, 15 January 2010). Design work is due to start this year and the restored gardens are due to open in three years.