The event marks the culmination of a three-year project to modernise this area of the gardens from its traditional layout, which was created and planted up in the 1960s. Head gardener Ross Barbour said: "In the original layout each bed contained a single variety of rose, which created problems with pests and diseases because of the monoculture."
The new design is based around diversity by taking away the majority of the grass and planting trees, shrubs and perennials to encourage insects.
The layout and planting scheme was designed by Barbour with Dale Goll of Golls Nurseries in Pitchill, which supplied perennials. Roses came from Bentley West Wholesale Roses in Leicestershire. Barbour said RootGro has helped to prevent blackspot on roses.
Barbour added: "I see the rose garden as the main hub of the 25 acre (10ha) garden due to its proximity to the house and the fact that it is seen by the majority of visitors to the hall, so I was delighted to have the opportunity to bring it more up to date."
The project began in 2007 when the grass from the old layout was dug up to make room for more trees, shrubs and perennials, which were planted in January 2008 along with the roses.