No; that's different from a non-compete. The practice of "gardening leave" is giving an employee a relatively long notice period (say, 3 months). If the employee gives notice, the employer tells them to stay home during the notice period; they are still technically employed during that period, however.
Gotcha; never been subject to gardening leave myself, but I always assumed it exists for the same purpose as a noncompete, i.e. to provide a 'cooling off' period to lessen the competitive impact that the exiting employee can have by switching to another firm. I assumed that since it's been around a while in finance that the "paid noncompete" idea became a negotiated part of the comp.
So funny to hear this. 3 month notice periods (in either direction) are bog standard in parts of Europe. And it's entirely normal to just keep working, training your replacement/finishing off stuff.
That's my point about it being funny. In one place a 3 month notice period is considered a gardening leave for special higher level employees and you still basically get escorted out of the building.
In other parts of the world it is just the bog standard notice period and nobody is escorted out of any building and expected to keep working during that 3 month period.