Lurie Garden

This guide to Lurie Garden in Chicago's Millennium Park explains the trick underfoot: three acres of tallgrass prairie growing in soil poured onto the roof of a parking garage, sometimes barely eighteen inches deep. It follows the firm Gustafson Guthrie Nichol, who won the 2000 design competition, and Dutch planting designer Piet Oudolf, who chose species tough enough to survive shallow soil and brutal winters. A fifteen-foot hedge of arborvitae, hornbeam, and beech walls off two sides of the garden, a nod to Carl Sandburg's old line about Chicago.