We’re all for living and entertaining outdoors, but as our gardens become semi-public spaces towards which guests gravitate, it’s nice to carve out a corner that’s just for you, a secret nook in which to unwind on one’s own. Any garden, from a grand acreage to a modest courtyard, can be designed with such a spot; the key is to create a sense of intimacy and sprinkle a little bit of gardening magic.