If anyone shouldn't be daunted by a small 890-square-foot patch of land, it's Rebecca Cole. After all, she has transformed the outdoor spaces of some of Manhattan's most demanding clients (including Christy Turlington and William Wegman), written two books on urban gardening, and made horticulture a hip downtown hobby since 1994, when she opened her Greenwich Village shop, Potted Gardens. But last winter, when this fast-track jack-of-all-plant-related-trades moved into her 1840s SoHo townhouse with its sliver of a backyard, she stopped for a moment. "Suddenly, I was looking at my own blank space," Cole recalls, "and thinking, Where do I start?"

Cole wound up taking the advice that she often shared with her clients and with readers of her books. "You can't get bogged down with the big picture," she explains. "You just have to do something; then each improvement will inspire the next step." In this case Cole began focusing on what she did and didn't like about the existing yard. Though she couldn't stand its new red brick floor, which clashed with her 160 year old townhouse--she did want a flat, open space on which to arrange chairs and tables for entertaining. So she decided on a big step: to replace that bright red brick with irregular slabs of soft, grayish tan stones, leaving narrow planting beds on both sides. Another thing that had to go: the white trellis overhanging the lower terrace near the back door. Cole ripped out the overbearing structure and replaced it with a simple iron arbor--a near duplicate of one that already existed at the far end of the garden.

A surrounding canopy of tall buildings limited her plant choices. But rather than mount and exhaustive search for the world's most unusual shade-tolerant species (and then go mad trying to keep them alive), Cole confidently repeated two basic combinations--spirea with ferns, hydrangea with hosta--throughout, mixing in English ivy, anemones, coleus, sweet-potato vine and eupatorium. She also relied on container plantings to enhance her borders. "Containers are great for varying height and texture. And because you can move them easily, they allow you to experiment."

Before long a theme emerged that was traditional enough to suit the house but, with a limited palette of greens, blues, and whites, cool enough to feel sophisticated. And Cole was back to her old self. "I'd be out there at three in the morning," she laughs, "just to meet some arbitrary goal I'd set for myself." She added fences, pillars and moldings to give the space its architecture, while old garden furniture provided its comfort. By summer the garden was finished. Or so it seemed. "I love all the aspects of this garden, but it will never be done," Cole says. "That's why I love what I do. Once you get started, anything--and everything--can be improved."

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