The garden will feature an entrance garden laid out like a web and planted as a perennial meadow, new lake which anchors the new visitor building/shop/cafe within the landscape, a water garden of interlocking streams and rocky waterfalls, the reconstruction of the historic walled garden, to include a therapeutic garden, vegetable garden and flower garden and a new learning centre.
Initial works will cost £30m and will include an entrance road, shop/entrance centre and work on the walled gardens.
Stuart-Smith said he first worked on plans for the garden 10 years ago for landlord Peel Holdings, who wanted to make it into a hotel/golf course complex. Stuart-Smith said he was glad the RHS had taken on the derelict garden because the old design would have "knocked the shit out of the place". As it is, he says the 10 acre walled garden is "moderately manageable", because it did not have stands of conifers planted by "Uncle Terry" or "lots of third rate park benches given by somebody 50 years ago", gave him more scope to design as he wished.
But he warned removing large areas of trees and rhododendron ponticum would be a "delicate PR matter" because the garden would change from a "mysterious and beautiful situation to become a working garden" and this would be done by "going backwards before going forward".
RHS director general Sue Biggs said: "These plans are at their earliest stages and may evolve as the garden develops, but they give a clear idea of the scale of our ambitions for this beautiful garden. I am grateful to Tom for his inspirational vision. We have an enormous task ahead of us but this plan will underpin and help us to shape everything that we do."
Stuart-Smith said: "RHS Garden Bridgewater is a perfect site for an RHS Garden, and these proposals are aimed at retaining the most historic aspects of the garden while reinterpreting and revitalising it."
On arrival to the garden visitors will be able to wander through a large garden planted as an extensive perennial meadow, with a network of web-like paths, which will lead them to the historic walled garden.
A new visitor building, to be designed by Cullinan Studio, and adjacent car parking facilities will be located at the southern edge of the site to avoid affecting the garden’s greatest assets – its existing structures, landscape and mature trees. A large open café terrace to the east will allow visitors to enjoy refreshments while looking over the water and into the heart of the garden.
The immediate surroundings of the new visitor building will make a strong connection between the walled garden at one end of RHS Garden Bridgewater and the historic terraces and lake at the other. A new lake will link the visitor building to the heart of the historic landscape of the garden, which is formed by the Nesfield terraces and the original lake. A water garden of interlocking streams and rocky waterfalls will further link the two and draw people along its length, creating a strong visitor circuit around the garden.
The outer walled garden will include a mix of ornamental and productive gardening, and a therapeutic garden, while the intermediate garden will concentrate on vegetable and fruit production. At the centre will be a flower garden based on the concept of the Paradise garden, complete with a lily pond. A new Learning Centre will be located at the north east corner of the walled garden.
The 154-acre RHS Garden Bridgewater is planned to open in 2019 as part of the RHS wider 10-year £160 million investment programme to achieve its vision. All plans at this stage are subject to lease and planning permission.
The RHS is working with the owners of the historic estate, Peel Land and Property, and Salford City Council, which is providing £19m funding, to bring the historic garden to fruition.