Using a range of recycled materials and bedding plants grown in the maximum security facility, 14 prisoners built the garden which features a train – the Maghaberry Flyer – and track, reflecting their journey from incarceration to release.

The work was carried out as part of the Horticulture City and Guilds course delivered at the prison by the Belfast Met.

The show garden competition is run similar to a Chelsea Flower competition and is marked to the Royal Horticultural Society gardens judging criteria. The Maghaberry ‘Moving Forward’ Garden picked up 88 of the 90 points which can be awarded.

Mark Holmes, head of prisoner activities at Maghaberry, said: “The prisoners’ commitment and enthusiasm for this project, right from the outset, has been fantastic. Their skills and hard work over a seven month period has not only turned a neglected area of the prison into a beautiful garden, but their efforts have also been recognised by the National Trust.

“The whole project has been a unique and special way to engage the men in purposeful activity as well as provide them an opportunity to gain skills and qualifications which might lead to employment when they are released.”

Richard Whiting, the horticulture trainer working for the Belfast Met at Maghaberry, added: “The purpose of the garden is to give the men somewhere to sit and reflect, to inspire thoughts of the future and moving forward in the right direction.

“The garden, with the theme ‘Moving Forward’, is essentially a visual metaphor designed to represent hope in the men’s journey, from imprisonment to release. A steam train and varied and colourful planting highlight the typical stages of progression throughout their sentence.

“The prisoners built the train and track from new and recycled material demonstrating resourcefulness with a ‘bug hotel’ to attract insects and wildlife highlighting its eco-friendliness.”

Presenting the Gold Award Certificate to Maghaberry Prison, National Trust judge Tammi Peek described the new garden as “wonderful”.

Ms Peek, who is also volunteering and partnerships manager at Mount Stewart, added: “We have been delighted to be involved with this project. It is inspiring to see how engagement with it has had such a positive impact not just on the grounds at Maghaberry but on the prisoners themselves.”

Director General of the Northern Ireland Prison Service, Ronne Armour, said: “I am delighted the show garden at Maghaberry has won this National Trust Gold Award.

“Part of the work of the Prison Service is to challenge people in our care and support them to change. Encouraging them through vocational skills will also help them when they are released, reducing the risk of re-offending and help to build a safer community.”