Landscape designer Shirley Watts is on a mission to green up her gardens. That doesn't mean she packs them with foliage. Watts is committed to green solutions that benefit the environment by preserving resources and by recycling materials.

For her redesign of Christine McCargar's Oakland, California, backyard (above), Watts recently earned Alameda County's Green Business certification. The site was challenging: a small, irregular space (only 12 ft. wide at the rear, 20 ft. wide close to the house, and 54 ft. long) hemmed in by houses.

"Since the garden was enclosed by buildings, it already felt like a room," Watts explains. "So I treated the garden like an extension of the house and split it into two living areas." Watts turned the rear "room" into an intimate space for relaxing and barbecuing. Recycled-steel trellises planted with climbing Asparagus retrofractus and papyrus screen views from neighboring windows. In the front, she created a stroll-through garden also meant to be viewed from McCargar's house. Raised beds, framed with the same recycled steel used for the trellises, overflow with colorful foliage. To separate the front and rear areas, Watts created a divider from two boxlike steel-framed racks used to store firewood.

The entire yard is paved with gravel ― a permeable surface that allows rainwater to seep into the soil instead of running into the street.

Design: Shirley Alexandra Watts, Alameda, CA (510/521-5223)