The garden is designed for a 2-acre site in Surrey, to complement a modern building design. Woodland edge and heathland plants surround the garden while the house is connected to the garden with grey decking walkways.
Views of the neighbouring golf course can be glimpsed through plantings of Betula utilis var. jacquemontii 'Inverleith' underplanted with Dennstaedtia punctilobula.
Finlay said: "I was so delighted to have my design 'validated' on an international platform; awards such as this help to launch new careers and for me it's now a firm step up on that ladder".
As the Gold Award winner Finlay will be awarded a scholarship and an award to be presented at the APLD's International Landscape Design Conference to be held in Santa Fe, New Mexico on 15 September.
Lead judge Greg Pierceall, Professor Emeritus at Purdue Landscape Architecture, said Finlay's project was "a stellar site design".
"At a macro scale looking at the total composition the project is great. The site spaces, plantings and surfacing are well done as is the layout and construction details.
"The project presentation is very well defined, outlined and presented. The plans, images, sections and references work well to convey the weave of plantings and areas within the site design.
Director of the London College of Garden Design Andrew Fisher Tomlin said: "We have always focused our design training to be world-class and Jane's award for a space that is both calm and yet full of vibrancy is a great reflection of what we want to deliver to our students. Jane's success is well-deserved and we hope will lead to even greater recognition".