"Gardening" books

The NY Times Review of Books threaded several books together under the heading of "gardening" but I don't think that Métis and vertical gardens were meant to fit the normal ideas about what is included in gardening. Indeed, the Times itself admits as much:

This year’s offerings, with a couple of notable exceptions, seem more to do with thinking about gardens than with the act of gardening. And only a particular kind of gardener (one who has to survive a very long period of dormancy) will have the patience to tussle with the vexatious question on several writers’ minds: What is a garden?

Still, the review is well worth the time for reading even if you don't have the inclination to read these particular books further.