Projects range from a modern Hong Kong roof garden to a contemporary British beach garden, with top names including Jo Thompson, Thomas Hoblyn, Andy Sturgeon and John Wyer.
Society chair Juliet Sargeant called the shortlist "very exciting" and reflected the wide variety of design projects that SGD members were involved in.
She added: "Members of the Society have the knowledge and experience to tackle whatever is thrown at them and the awards are a celebration of their creativity and commitment to excellence.
"Most of the work of garden designers is never seen as it is undertaken behind the walls and gates of private houses. The awards are a unique opportunity to take a glimpse into the world of garden design."
There have been 95 entries so far and two categories – Student and Designing for Community Space – remain open for entries until 12 August.
There are 18 awards up for grabs and winners will be announced on 24 January next year. Tickets for the ceremony go on sale in October.You can see images of the shortlisted projects here.