Plans for Manchester’s new Sky Park spring to life with planting underway on Castlefield Viaduct

Press release
Manchesters new Sky Park
Published : 17 Jun 2022

A new urban sky park on Manchester’s Castlefield Viaduct is springing into life with thousands of plants being added to the derelict structure.

National Trust gardening specialists and apprentices are busy planting 3,000 trees, flowers and shrubs on the viaduct as part of plans to ‘green’ the historic landmark and bring more nature to the Castlefield area of the city. 

Due to open to the public in July, the Trust aims to turn the viaduct into a temporary urban park and capture visitors’ opinions to help determine the longer-term future of the Grade II listed structure. Visitors will experience a variety of planting displays as they walk along the viaduct, moving through an area of native plants, shrubs and trees, to a ‘show garden’ setting at the end. 

In addition to creating a place where people and nature meet, the new experience will also celebrate the industrial heritage of Castlefield. The design of the planters gives a subtle nod to the industrial architecture of the viaduct which was built in 1892 by Heenan and Froude, the engineers who worked on Blackpool Tower. The shape of the planters mirrors the curve of the viaduct and their width is the same as the railway tracks that once transported goods across the structure to the Great Northern Warehouse. A section of the viaduct will be left untouched to provide a sense of how nature has reclaimed the space since the site closed in the late 1960s.

Plants take inspiration from what had already started to grow on the viaduct with shrubs, ferns and grasses providing a frame for more colourful seasonal planting. Sections of the planting will mimic the diamond shape of the viaduct’s criss-cross steelwork, achieved through diagonal blossom hedges and other plants. 

The original ballast surface is being incorporated into the scheme with 280 sandbags built up at varying heights to create planters which are being brought to life with Broom, fennel, grasses, ferns, euphorbias, sedums, fleabane, buddleja, teasle, liriope and Phlomis.

A canopy is also being created using 600 half-hardy annual climbers and others including hops and clematis which will tumble down. Many of the plants making up the canopy have been grown at the National Trust’s Plant Conservation Centre, with other plants coming from nearby Trust property, Dunham Massey. 

Pamela Smith, Senior National Consultant for Gardens & Parklands at the National Trust said: “We’ve reached an exciting stage in the project to transform Castlefield Viaduct into a green space for the people of Manchester. Creating a garden on an industrial heritage structure such as this is untested territory for us and we’re intrigued to see how the plant life will take to its new surroundings. 

“In addition to greening up a heritage structure, we’re celebrating Manchester’s history adding the county flower, cotton grass, to the viaduct as well as fern species once collected by Manchester suffragist and botanist, Lydia Becker.”   

The garden team will be trying out new planting techniques, working with limited growing depths and untested growing conditions. Due to weight limits on the structure, the National Trust is also using a specially commissioned, extra light peat-free compost in all its planting on the viaduct. The planting will take a little while to establish and will develop through the seasons under the care of the Castlefield Gardener and volunteers. 

Amy Watson, Castlefield Gardener at the National Trust said: “Castlefield Viaduct is unlike any other garden in the National Trust’s care and we’ll be keeping a close eye on the garden to see how it gets on over the next twelve months. I’ll be working with a team of dedicated volunteers and apprentices to plant bulbs on a regular basis and adding to the planting to make sure there’s plenty to see throughout the year. We’ll also be working closely with our partners to see how their gardens are responding to their unique surroundings”

Four areas of the viaduct have been handed over to partner organisations to create their own unique gardens[2] for visitors to enjoy. Known as ‘partner plots’ these areas by Urban Wilderness, the Science and Industry Museum, City of Trees and Castlefield Forum are in the final stages of completion.

Urban Wilderness are working with Manchester based charity, 42nd Street, supporting young people who have suffered mental health challenges. The ‘Garden of Possibilities’ features a geodesic dome and plants which are known for having positive effects on mental health including nettle, feverfew and lemon balm. 

The Science and Industry Museum has filled its garden with plants that engage the senses and encourage visitors to take an active role exploring the local historical landscape. The planting takes inspiration from the museum’s globally significant site, which was once a bustling station at the terminus of the Liverpool and Manchester Railway, the world’s first steam-powered intercity railroad. From the vantage point of the viaduct, the roof tops of these historic buildings are visible. 

Plumes of steam from the locomotives, which would have left trails across Manchester’s skyline, are represented with fluffy white plants such as sanguisorba albiflora. Blue flowering plants such as lobelia are designed to cascade and flow, representing the essential relationship the first railways had with water, and decorative pipework and hand-cut trellis panels will display patterns to evoke the connectivity brought about by the rail networks. 

The theme of the City of Trees partner plot is ‘Trees – Past, Present and Future’. It aims to showcase a variety of trees, shrubs and flowers that have been used throughout the Industrial Revolution, as well as displaying trees which are significant in Manchester today, and those that will play a role in the city’s response to climate change in the future. Plant species include box, gooseberry, damson and comfrey amongst many others.

Castlefield Forum have worked with landscape architects BDP to create their garden. The informal planting scheme is spread across two raised beds with plants of the same variety grouped together to provide a natural, layered effect. Their chosen plants mirror the distinct features of Castlefield in both colour and scale. Highlights include blue sages, Verbenas and purple Alliums reflect the steel-grey tones of the viaduct and water beneath, whilst orange yarrow, bold red daylilies and Heleniums represent the terracotta brick of the Victorian warehouses and exposed seams of sandstone upon which the Roman settlers constructed their fort in Castlefield in 79 AD. 

Working with the local Saul Hay Gallery, Castlefield Forum have also commissioned a unique artwork to form a central part of their area on the viaduct. 

The temporary urban park opening this summer will see green space stretch halfway across the elevation of the viaduct.

During this time, visitors will have the opportunity to explore part of the structure and find out more about the viaduct’s heritage, the city’s long relationship with plants and trees and learn urban gardening tips.

The charity also aims to capture visitors’ opinions to help determine the longer term future of the Grade II listed structure.

Sophie Wardell, Urban Places Programme Manager at the National Trust said: “So much hard work has gone into getting the viaduct to this point and we couldn’t have got this far without the support of our partners and those who have helped make this happen for Manchester. A little over 12 months ago we’d only just shared the artist illustrations of what the viaduct could look like, and now it’s becoming a reality. This first year is an experiment for us to see what people want Castlefield Viaduct to be in the future and we’re excited to hear what ideas they have.”

Lead architects on the project, Twelve Architects & Masterplanners, have been working with the National Trust since 2021 to help the charity design the first phase of the project. 

Irina Adam, Project Architect at Twelve Architects & Masterplanners says: “It’s such a joy to see this iconic structure being given a new life as well as adding to the diverse urban fabric of Manchester. This pilot phase of the project is designed to show visitors the viaduct in its existing state while also taking them through a series of different spaces that show how it could be transformed. We’re excited to hear people’s ideas for how a larger viaduct public park could be, and to work with the National Trust on future phases.”

Costing £1.8 million, the pilot has been made possible thanks to funding raised by players of People’s Postcode Lottery, as well as public donations which will cover two-thirds of the build costs.

Laura Chow, Head of Charities at People’s Postcode Lottery, said: “I’m delighted that Castlefield Viaduct is coming alive for the people of Manchester and that funding raised by our players is helping to make this happen. Over the past few years we’ve all seen how important access to green spaces and connecting with nature is to our wellbeing, so our hope is that by supporting this project we make this possible for even more people."

The plans for Castlefield Viaduct are part of the National Trust’s Urban Places work to increase access to parks and green spaces in, around, and near urban areas, so that more people are in easy reach of quiet places with wide open skies.

When the first phase opens next month, 100 people a day will be able to visit. Entry onto the structure will be free, but a booking system will be in place to help manage numbers. As part of the experience, visitors will be able to join a guided walk on the viaduct.

Overseeing the construction of the temporary urban park is Russ Forshaw, Group Operations Director at MC Construction. He says: “The regeneration of Castlefield Viaduct is full steam ahead and the team on site have been working tirelessly to bring National Trust’s vision to life. We are thrilled with the progress so far as we move into the final stages of the project.

“As a local SME which has just celebrated our 50th year in business, we view this as a landmark project, adding to our legacy of works within the city of Manchester.”

The National Trust will also need to raise funds to support the future of Castlefield viaduct. To find out more about ways to support the project, contact 

To find out more about Castlefield Viaduct, visit: