Calcot Kitchens, the outside catering arm of Calcot Hotels, has won a five-year contract to operate the restaurant at the National Arboretum in Gloucestershire.
The Forestry Commission, which manages the historic tree and shrub collection at Westonbirt, appointed Calcot Kitchens (formerly Williams Kitchen at Calcot) to run its public restaurant and café facilities after what it described as a "rigorous tender process".
Michael French, Calcot Kitchens general manager, has been overseeing a revamp of the facilities ahead of the contract beginning on 18 March.
He said: "A complete refit is now underway ahead of the Westonbirt Restaurant's re-opening when a totally new front-of-house design, branding and catering concept will be revealed, drawing strongly upon its arboreal setting and rarefied environment.
"Similarly inspired by the impressive surroundings, the menu offering and food presentation will also in its turn accentuate the overall Westonbirt experience for visitors by instilling a real sense of destination."
The 100-seat Westonbirt Restaurant, with a further 200 places outside, will benefit from the 350,000 visitors that are expected annually.