From a flower-filled moat at the Tower of London to a rooftop community garden on the Old Kent Road, the work of the landscape designer, horticulturist and educator Nigel Dunnett, who has died aged 63 from cancer, showed how urban landscapes could be visually dramatic, ecologically rich and experientially uplifting. Dunnett’s deep plant knowledge, design acumen and advocacy of biodiversity helped change how cities, institutions and public audiences understand the role of landscaping and naturalistic planting.

As a pioneer of ecological and sustainable approaches to gardens, landscapes and public spaces, he saw planting not just as a cosmetic afterthought but as a living, evolving and inspiring part of urban life.

His Superbloom project for Queen Elizabeth II’s platinum jubilee in 2022 involved 20m carefully selected seeds, including poppies, corn marigolds and cornflowers, sown in the vast moat that girdles the Tower of London. Generating a vibrant, changing panoply of flowers over the summer months, it was inspired by Dunnett’s travels to California in 2019, during which a rare “superbloom” of wildflowers transformed the terrain across the American south-west. It demonstrated the appeal of seed-based, naturalistic planting at one of the UK’s most historically resonant landmarks.

Another “Elizabethan” project was the planting design of the Queen Elizabeth Olympic Park for the London 2012 Olympics. This brought large-scale perennial meadows and long-season planting to global attention and became a reference point for how public landscapes could cultivate biodiversity and resilience, while making an indisputably dramatic visual impact. He also installed a garden to commemorate Queen Elizabeth’s diamond jubilee at Buckingham Palace, conceived as a stretched diamond grid, and he attended its opening alongside the monarch.

At the time of his death, Dunnett was working as planting designer and horticultural consultant for the Queen Elizabeth memorial in St James’s Park, designed by the architects Foster + Partners with the landscape architect Michel Desvigne.

Dunnett’s approach blended horticultural depth with ecological purpose and was attuned to nature, using perennials, meadows, seed mixes and layered planting systems to devise landscapes that changed through the seasons and responded to the realities of urban maintenance.

As well as bringing life and colour to nationally significant locales, he worked on a more modest and quotidian scale: gardens, urban parks and neglected spaces on and around buildings. His planting scheme for Peveril Gardens, Southwark, transformed a disused playground above some formerly derelict garages into a rooftop community space, overlooking a busy roundabout on Old Kent Road in London.

With the architects Sanchez Benton and the Mexican artist Gabriel Kuri, Dunnett transported the garden’s visitors far from south London, selecting plants from all over the world to reflect the richness of the local community: kniphofias from Africa, nandinas and bergenias from Asia, and astelias from New Zealand.

“I thought it would be a nice metaphor to have a cosmopolitan mix of plants from virtually every continent that would come together and coexist,” he told Gardens Illustrated in 2024. In a similar spirit, self-seeders and blown-in plants were also encouraged. Walls of eye-popping tangerine recalled the buildings of the Mexican architect Luis Barragán.

Dunnett’s wider portfolio ranged from designs for Battersea Power Station and the Barbican to landscaping for the Italian city of Bergamo. A major scheme for reconfiguring Grosvenor Square in Mayfair, which will introduce flowering lawns and new woodland planting, is due to be completed later this summer. He was also involved in the design of several award-winning RHS Chelsea Flower Show gardens. In 2025 he created the Hospitalfield Arts Garden for Chelsea as a “dunescape”, which took its cue from the sand dunes of the east coast of Scotland, while reflecting the current interest in using sand and mineral materials as growing media to encourage diverse and resilient planting.

Throughout his career, Dunnett was an energetic advocate of public engagement, becoming well known through broadcasting and television appearances, including regular stints on the BBC’s perennially popular Gardeners’ World.

Born in Ipswich, Dunnett was the eldest of three siblings. His parents, Robert, a metalwork instructor, and Margaret, were keen gardeners, who opened up their own garden to the public as part of the National Garden Scheme. When he was five they gave Nigel a small patch in which to cultivate salad plants. He also enjoyed reading about gardens, discovering the plantsman Christopher Lloyd’s classic The Well-Tempered Garden at an early age. “It just completely changed my view of what gardening was – and made me laugh out loud,” he told the Gardens Illustrated editor Stephanie Mahon in a 2024 podcast.

His family later moved to Selling, near Faversham in Kent, where the village school ran a nature walk on Friday mornings, which sparked his love of wildflowers. “The teacher pointed out wildflowers, but she’d use the common names, like dog’s mercury and lady’s smock and cuckoo pint. Giving the plants names gave them personalities and to me they came alive.”

Dunnett studied botany at the University of Bristol, graduating in 1984. This was followed by postgraduate study for a master’s in landscape ecology and landscape management at Wye College in Kent. In 1994, he joined the department of landscape at the University of Sheffield, obtaining a PhD in animal and plant sciences in 1996. By 2011, he had become professor of planting design and urban horticulture. Working alongside a fellow professor, James Hitchmough, Dunnett was an influential figure at the university, helping to train landscape architects, garden designers and landscape managers. His research explored vegetation and planting design techniques that included green roofs, rain gardens and long-term ecological monitoring.

Sheffield was particularly close to his heart. In tandem with a distinguished teaching career, he was involved in the Sheffield Grey to Green project, which converted 1.6km of former highways into Europe’s biggest retrofitted sustainable drainage system. Working with the landscape architect Zac Tudor on the planting design, he created the UK’s largest urban green street. Speaking to the BBC, Dunnett said the idea behind the project was to “make Sheffield different, really make it a garden city”.

In 2020, he was made an honorary fellow of the Landscape Institute and, in 2023, became a Royal Designer for Industry, a select coterie limited to 200 individuals at any one time. He was also awarded a lifetime fellowship of the Royal Society of Arts. He wrote a number of books, including Naturalistic Planting Design: The Essential Guide (2019) and The Dynamic Landscape, with Hitchmough, first published in 2004, with an extensively revised edition produced in 2025.

Recently completed is a roof garden for patients in the critical care unit at King’s College hospital, London, conceived by Dunnett and his co-designer, Sarah Price, as a “ward in a meadow”, a fully functioning ward space in an external garden setting.

Whether in the public or private sphere, Dunnett regarded gardening and planting design as an expressive process. “I see the creation of a garden and the act of nurturing it, as not just a practical maintenance thing and not just a scientific thing; it’s an artful thing,” he said in 2024. “There’s a good proportion of gardeners who are artists. It’s not just horticultural maintenance; it’s something that touches people and allows them to express themselves.”

He is survived by his second wife, Marta Herrero, an academic, whom he met when they were both working at Sheffield University; and two children, Alex and Jack, from his first marriage.