Wilson's Grand Award was his third at the ceremony in The Millenium Hotel, Kensington, London, on 24 January.
His contemporary garden in Hertfordshire was also named Large Residential Garden and the winner of the People’s Choice Award, voted for by readers of Homes and Gardens magazine.
The judges called it "a garden full of surprises" and praised the "serene composition" and "exciting and challenging planting combinations" in the garden's wide variety of contexts.
An Amanda Patton-designed private garden in Somerset was the project that the judges felt most successfully achieved one of the central foundations of good design – a sense of place. The garden, which also took the award for best Medium Residential Garden, was described by the judges as "A simple idea expertly integrated into its surroundings."
On presenting the award, judge Richard Sneesby said: "The beautiful planting, creative use of traditional materials and craftsmanship, and an intelligent judicious nod to the 21st Century, remind us of where we are now and where we have come from."
Society Fellow Andy Sturgeon also had a good night, scooping awards for three separate projects in the Planting, Hardscape and Small Residential Garden categories including a series of modern roof terraces set against the Hong Kong skyline.
Garden and landscape photographer Andrew Lawson was given The John Brookes Lifetime Achievement Award, named after one of the society’s life members and granted to an individual who has made a outstanding contribution to the landscape and garden design profession.
SGD chair Juliet Sargeant said the decision, made by the council of the SGD had been unanimous, and said stress drained away when she looked at one of his photographs.
"Through his beautiful work, Andrew has not only highlighted the achievements of many garden designers over the years, but he has also inspired a generation to greatness in their designs. We all felt he was a very worthy recipient of the award."
Introducing the ceremony, Sargeant said the awards had "burst onto the landscaping scene", introducing four new categories this year.
"Members of the Society of Garden Designers undertake every kind of exterior project that you could imagine. Their mission is to enhance landscape for the good of everyone in society, while delivering excellent service to the owners of individual gardens.
"I am tremendously proud of the excellent standard of entries recieved and the exciting showcase this has become."The president-elect of the Landscape Institue Noel Farrer also gave a speech acknowledging the connections between the two professions and calling for greater cooperation.
There were 18 awards in total. The winners were:
- Student Nick Morton
- Paper Landscapes – Nicola Greaves
- Renovation – Mark Fenton
- Hardscape – Andy Sturgeon
- Lighting – Charlotte Rowe
- Big Design Small Budget – Christine Whateley.
- Designing for Community Space – Jointly went to Montpelier Community Nursery Garden and Gibbon's Rent projects.
- Planting Design – Andy Sturgeon
- Future Designer – Jo Thompson
- People's Choice – Andrew Wilson.
- Public or Communal Outdoor Space – John Wyer
- Small Residential – Andy Sturgeon
- Medium Residential – Amanda Patton
- Large Residential – Andrew Wilson
- International – Sally Court
- Judges' Award – Amanda Patton
- Grand Award – Andrew Wilson.