“The transition from the interior to the exterior is extremely important,” says Martin Wade, who founded his design company 24 years ago. To create a pleasing flow between inside and out, Wade might repeat a colour, wood stain or architectural motif. In gem-size Riverdale and Annex gardens, where every inch counts, structural items often serve double duty—a bench stores cushions; a wardrobe folds down, Murphy bed style, to act as a buffet table. A small- to medium-size urban garden can run between $50,000 and $75,000; to protect your investment, the firm offers garden maintenance—they will do everything from weekly weeding to seasonal pruning to even coaching wannabe green thumbs to do it themselves.