The simplest plantings become more artful when highlighted by metallic structures. Modern materials assume an ancient sculptural form to frame foliage when anchored into evocative urns. These gold- and copper-wire obelisks are made of decorative wire. The 6-gauge aluminum wire, which is more malleable than steel or copper, is thick as a stout plant stem and available in a treasure trove of colors. To echo the subtle gleam, brush a plain plastic pot with a thin coat of metallic paint.