Keep the garden vertical. That's why it's good to look for shrubs and trees that max out interest as they grow up, not out. Try dwarf varieties for a small backyard, as well as more columnar evergreens (bonus—they boost wintertime interest, too).
Quick Privacy Garden Plan This mix of trees, shrubs, and perennials makes a lovely -- and quick-growing -- screen for privacy or to mask an eyesore. As a bonus, it also attracts birds! For the back of our lawn.