According to Wikipedia Garden leave or gardening leave:- describes the practice where an employee leaving a job – having resigned or otherwise had their employment terminated – is instructed to stay away from work during the notice period, while still remaining on the payroll.
Gardening leave is a term that originated in the UK and was adopted in Australia & NZ too. When I resigned back in October, 2016 I didn't think it would happen to me. After all I'm leaving a US focussed role to run a Sydney agency. Yes on a Global scale we compete, but from my view point, my specter of influence doesn't overlap.