The works are taking place at Culzean Castle, in Ayrshire, the historical home of the Kennedy clan chief.
Other measures include restoration of celebrated herbaceous borders, creation of new orchards and bringing new prominence to an ancient sundial.
Planting for the two-year project has already got under way, with the aim of transforming the land back to a bountiful growing space and regaining its former glory as a ground-breaking horticultural showcase.
The redesign is focused on the North Walled Garden and aims to add a 21st-century twist to the historical landscape.
A mixture of traditional and modern growing techniques and plant species will be used in the new plan, producing the likes of Indian and Chinese tea, botanicals for brewing and a wide range of fruit and vegetables.
The project is being undertaken by the National Trust for Scotland (NTS), which has been caring for the property for the past six decades.
Tim Keyworth, gardens and designed landscapes manager for NTS, said: “Built in 1782, the walled garden at Culzean is one of the largest in Scotland and is a key garden in the National Trust for Scotland’s care. This project will enable continuation of an overall design that captures the spirit of the gardens at Culzean.
“Key to the redesign of the North Walled Garden has been to return this area to being a productive space. Historically this part of the garden has always been productive and due to a number of factors this has been largely lost to time.
“The overall aim of the project is to create one of the best walled gardens in Scotland. It should become the most productive and aesthetically pleasing example of its type within the National Trust for Scotland.”
When the revamp is complete, home-grown produce such as tea, fruit and nuts will be served up in the castle’s cafes and restaurant.
The majestic building that stands today was designed by renowned Scottish architect Robert Adam for the chief of the Kennedy clan, the Marquess of Ailsa, and completed in 1792.
It has links former US president Dwight Eisenhower, who was given a lodging there by the Marquess in recognition of his efforts during the Second World War.
The estate had a reputation for cutting-edge gardening, growing the likes of nectarines, peaches and apricots which the Kennedy family would have shipped to them when away from their Ayrshire seat.
Iain Govan, head gardener at Culzean, said: “One of the things that’s really unique about Culzean is that it has never been out of gardening.
“A lot of historical properties have fallen into disrepair in the past and then they are brought back to life to represent a particular period. Culzean is great because it has never fallen into disrepair, and has been continuously evolving so what you see today isn’t a recreation. It’s the result of ongoing development of the garden over the centuries. The walled garden dates from 1778, and it has been progressing from then until now. We are just the latest phase to keep the garden innovative and fresh.”
The castle and its 660-acre grounds were gifted to the NTS in 1945 and remains a popular visitor attraction.
An image of the castle appears on the back of £5 notes issued by RBS.