For all the drama they add to a landscape, hillsides present their own set of problems. Here's how to cope with a steep learning curve.

In Robin Benson's garden in the Hollywood Hills, purple hop bush and silver echium climb a hill, their colors echoing the succulents and shrubs that have been planted below to soften the hard lines of a poolside retaining wall.

In another corner, grape ivy cascades over a courtyard wall.

Designer Judy Kameon wanted Benson's stairs, which are made of landscape ties, to wind through a sea of plants, slowing the uphill walk and inviting visitors to enjoy the colors and textures of grasses and fragrant herbs. The repeated forms and hues of the sprawling plants lead the eye through the space.

The first rule of stair-side plants: What grows by your feet gets extra attention. The etched leaves of Hedera helix 'Needlepoint,' the gold-plumed Stipa tenuissima, and Lavandula 'Grosso,' which releases its scent when rubbed, all reward close scrutiny.

At the entrance to I'Lee and Tony Hooker's property, a stone wall and basalt stairs by artist Edwin Hamilton curve down toward the house.

The backyard was densely planted by I'Lee with her favorite flowers, including hydrangeas, dahlias, and irises.

Among a hilltop's rewards is an open vista: The Hookers look across Tiburon's harbor to San Francisco. To enhance the view, I'Lee framed it with Eastern redbud and Japanese maple trees. Gold Acorus gramineus 'Ogon' sprouts between the stones.

To avoid blocking her view, Hooker chose small to midsize plants for the upper hillside, primarily viburnums, begonias, and hydrangeas. She loves to look down through trees but was careful not to add any that would grow too tall. Small Japanese maples, which she keeps well-pruned, have proved ideal.

The lowest level of the Hookers' garden features a spacious covered swing topped with abundant climbing roses and clematis, a half-hidden resting spot at the end of a path.

Designer Topher Delaney laid out the pool and the retaining wall for the poolside garden, which is now covered with trumpet vines. Plantings of roses and geraniums make the wall seem to recede into the hillside.

An ideal mix for erosion control includes trees, shrubs, perennials, and ground covers. Hooker began with 15 existing oaks and planted Japanese maples and a tricolor beech tree as further vertical accents. She then massed succulents, Mediterranean herbs, and ornamental grasses around them to create blocks of color, and variegated furcraeas for a shock of gold.

The poolside Japanese maple adds a burgundy contrast to the largely green scheme, and its color is reiterated around the hill in the shadowy tones of barberry, dark dahlias, and abutilon. Yellow and chartreuse foliage add sunny counterpoints.

Lounge chairs reward those who make the trek down the slope. Visitors have a choice of paths to return on the leisurely main zigzag or a shorter, straighter scramble.

For his rocky incline in Napa, California, Jack Chandler trucked in soil to create terraces that are retained with steel plates. Close to the house, the walls spill over with euphorbia, nepeta, daylilies, and xylosma, an evergreen shrub.

Higher up, stachys, cistus, marjoram, and salvia lead to a citrus grove and a pergola.

In Greenwich, Connecticut, designer Florence Boogaerts conjured a grotto from a stony outcrop. The all-green planting requires almost no maintenance. The bold leaves of three cultivars of hosta are woven into a tapestry of pachysandra, ferns, and pots of clivia.