Contrast shapes. Pair mounding and spiky plants, such as catmint with phormiums, then tuck in plants with fine leaves to add texture.
Expand your palette. “Because there’s so much green in the natural landscape, I add foliage for contrast—blue, burgundy, orange, and chartreuse,” Baumann says. To lighten shaded areas, use plants with variegated leaves.
Make your own art. To build his wave walls, which hide existing concrete retaining walls, Baumann sketched the waves on sheets of plywood, then took the numbered panels to a metal fabricator.