Featuring more than 4000 variations of Mediterranean plants, the garden is said to be more resilient to climate change and is now open to visitors.
Selected by the award-winning designer Andy Sturgeon, the plants - including perennials, grasses, trees and shrubs from the Mediterranean and similar climates such as South Africa, North Korea, Chile, China and Australia - will be able to cope better with hotter and drier weather in the summer and wetter weather in the winter.
Andy Jasper, the charity's head of gardens and parklands, said they hope visitors will "be inspired to future-proof their own gardens" as well.
“With more intense weather events, including drought and floods, predicted, our gardens need to change to better tolerate extremes.”
Chelsea Flower Show gold medalist and Societ of Garden Designers award winner, Mr Sturgeon, has been working on the project since 2016 too.
He said: "In the UK we can expect warmer summers with prolonged dry periods and drought, but also an increase in very wet days, particularly in winter.
“We need to start changing the way we garden and I have taken the opportunity to embrace this at Beningbrough.
“What we have created is in effect a vast gravel garden that sits comfortably in the historic setting – I hope that it will feel quite timeless.”
“I think the success of this garden comes from the marriage of the ancient red brick walls, the presence of the Hall towering over it and the elegance and textural beauty of the new planting.”
The team recognise the irony of creating such a garden after one of the wettest years to date in the UK. A large tank has been installed under the garden to collect excess rain and release it to prevent flash flooding.
Built in 1716, the stately home itself reopened in 2023 after almost two years of refurbishment.
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