Things were less simple in the north-facing backyard. Barb's big challenge there was figuring out what to do with the knoll, a 25-by-15-foot oval of almost solid rock that drops off into a ravine. The little soil it had was thin and sat in full sun. Few plants can handle these dry, unforgiving conditions, but Barb decided to chance it. Thyme took, as did low-growing barberry, veronica, and sedum. In one particularly inhospitable area, she skipped digging altogether and put an ephedra and a blue rug juniper in a huge pot, with two empty vessels nearby as accents. Most of these plants go dormant in winter, except for the whimsical juniper topiary and shrubby dwarf pines, which look handsome when lightly dusted with snow.
Surrounding the knoll, Barb added a small stretch of lawn and ringed that with a deep perennial border filled with easy-care plants, including purple coneflower, coral bells, barberry, lavender, and daylily. "In an 8-foot-deep border, I start in front with low groundcovers, then 12- to 18-inch plants in the middle, and then plants in the 2- to 2½-foot range at the back," she says.
Shown: In the backyard, a border blooms in three tiers: plume poppy, yellow-flowered helianthus, and barberry 'Helmond Pillar' at the rear; English lavender, 'Big Sky Sundown' coneflower, and daylilies in the middle; and, down front, dwarf barberry 'Bagatelle,' coral bells 'Obsidian,' hardy geraniums, and colorful annuals.