Thompson, who scooped a certificate of merit for her design at this year's show, will create the Staycation Garden for the Caravan Club.
Other designers who have confirmed projects at next year's show include Andy Sturgeon and Arne Maynard, who is designing for Laurent Perrier. Chris Beardshaw will create a garden with staff and students from learning disability charity Furzey Gardens.
Two members of the Olympic Park design team have also confirmed show gardens at the event. Nigel Dunnett will create the Blue Water Garden for Royal Bank of Canada and Sarah Price is designing a garden for the Daily Telegraph.