It isn't just wildlife that's experiencing a shrinking of habitat. With 7 billion humans now on the planet, the space between us for sprawling flat gardens is diminishing rapidly as well.
The future of gardens isn't out but up. Exploiting non-traditional green spaces and otherwise reforesting urbanized hardscape, indoors or out, makes for exciting new possibilites.
A vegetable garden constructed from rain gutters:
The jungly offices of Herman Miller:
For the love of Ivy: Princeton, New Jersey.