The West Sussex site had seen many changes since its heyday in the Edwardian era, suffering a long decline during the 20th century and the great storm of 1987.
The pair (Custodian Awards host Sue Ireland, open spaces director at City of London) have dedicated a lifetime to transforming 37ha of neglect and dereliction, working within the historic framework while adding their own contemporary contributions.
Projects include the two-year restoration of the kitchen garden, including 13 Victorian glasshouses; a walled garden with espaliered fruit trees; reinstating a 300ft Edwardian pergola by Harold Peto and adjoining sunken garden; and rethatching and reflooring the summerhouses.
The ornamental gardens are designed for ease of maintenance and attractiveness, with 14ha of sweeping lawns, shrubberies and herbaceous plantings. Mown grass has been converted to wild flower meadow with 500,000 bulbs naturalised and a new visitor centre added.
The spring garden derives special character from the River Lavant and small tributary, a "winterbourne" with intermittent seasonal watercourse. Clearance of the 1820s flint and stonework, virtually lost in encroaching vegetation, was the first step. The derelict walls and river floor were deconstructed and painstakingly rebuilt over four years.
The wild garden has been restored while a tree-planting programme in the landscape park has reinstated the lost ornamental planting of the 19th century. Work is now ongoing to highlight the collection in the St Roches Arboretum.
The renovation of the gardens has taken passion, imagination, leadership, deep horticultural knowledge, skills and determination. As custodians, Jim and Sarah have committed a lifetime's work to build on the horticultural foundations laid down by previous generations to ensure a lasting legacy for the future.
They head up a team of nine permanent gardeners, 40 UK and international volunteers (eight per day). The team has carried out hard landscaping, tarmacking, metal fabrication, the vast bulk of arboricultural work and the wide range of horticultural activities. Garden visitors are 60,000 annually, with the revenue used to defray running costs.