The modern tract home is a marvel. Dream kitchens with cabinet space to spare, a full arsenal of appliances, and countertops big enough for the most ambitious meal preparations. Master suites luxurious enough to hide out in all weekend. Bathrooms and closets the size bedrooms used to be. Home offices.

There's a flip side, of course. Such amenities require floor space. To get it, these generously scaled homes hog most of their lots. What's left for the gardener is often minuscule: a mouse pad-size entry, a backyard only marginally bigger, and spaces no wider than hallways on either side of the house.

Older houses often share the small-yard dilemma with tract houses. As their owners remodel them by raising the roof a story or two and pushing out walls as far as municipal codes allow, little space is left over for outdoor living, play, or planting.

Garden designers have become masterful at making the most of such downsized spaces. On these pages are some of their design ideas and advice for making small gardens live large.