The 100m walk has been replanted with rare Penjerrick rhododendrons, which were micro-propogated in Cornwall.
It is expected to create a floral spectacle to match the famous Laburnum Arch. The earliest and longest of its kind in Britain at 55m, the Laburnum Arch draws in around 50,000 visitors for the three weeks when it is decked in golden flowers.
The 100m Penjerrick Walk forms part of Furnace Hill, a secret part of the garden overlooking the River Hiraethlyn and the grand house. It will open to the public for the first time in spring 2017, creating an extra 8ha for visitors to explore.
Penjerrick Walk is a recreation of the avenue of creamy white hybrid Rhododendron 'Penjerrick' that was originally planted by Henry McLaren.
Former Bodnant head gardener Troy Smith was inspired to reinstate the walk after discovering a speech written for the Royal Horticultural Society by Henry McLaren, 2nd Lord Aberconway, from 1950: "If I could switch the clock to any season of the year to enjoy a two minute walk at Bodnant, my choice would be the Penjerrick Walk in the first week of May."
Smith's successor John Rippin, is now helping to turn the idea into a reality. The Rhododendron originates from the Himalayas and the Penjerrick is a rare hybrid bred at Penjerrick Garden in Cornwall.
With help from the Rhododendron, Camellia and Magnolia Group of the RHS, the team at Bodnant has been able to micropropogate plant material from the remaining Penjerricks at the garden at a specialist laboratory in Duchy College, Cornwall. The plants, which are currently no more than 60cm high, are expected to be in full bloom within ten years.
Rippin said: "We have many thousands of rhododendron species from across the world at Bodnant Garden and the team goes to great lengths to conserve and tend to the plants to ensure the grounds look incredible all year round. The Penjerrick is an especially significant plant to the history of the garden and is a rare breed within its species.
"Since 2012 the team here has opened up four new parts of the garden and we can't wait to open Furnace Hill for visitors and will be eagerly waiting for the Penjerrick Walk to come into full bloom. The support from Duchy College and the RHS has been invaluable in making this happen."
Justin Albert, director of National Trust Wales, said: "Collected by intrepid plant hunters from as far back as 300 years ago, our precious plant life stands as testament to the vision and passion for plants shared by generations of owners and gardeners.
"This fantastic project at Bodnant Garden is just one of the many and varied conservation projects that our teams of gardeners and volunteers are undertaking at our gardens across Wales to restore and preserve plants from across the world for visitors to enjoy. Our ultimate goal is to look to return rare species we have conserved back to their places of origin, such as the Chinese Acer griseum found in Dyffryn, brought from China by the famous plant hunter Ernest Wilson."
"We really do offer a world of gardens within Wales and June is one of the best times to see our gardens in all their glory, so we hope by sharing the stories of our rare plants we will inspire people to visit."