If you'd like to grow a living wall but are worried about high water requirements, you should know that it's possible to design an attractive wall using a variety of drought-resistant plants.
"Many common vines and ivy are pretty and do well with little watering," says Lynn Capouya, a landscape architect in Newport Beach who is the author of "Garden Guides," a guide to low-water, low-maintenance plants and their care. She suggests considering Boston ivy, bougainvillea, cat's claw vine and Lady Banks' Rose.
There are many ground covers that are also hardy and long-lasting, says Jeffrey Garton of Paradise Designs in Dana Point. "Try Scottish and Irish moss, Veronica repens, which is an evergreen ground cover that trails some, and Vinca Minor, which also trails and has a bluish-lavender flower."
If you want to add something edible to your living wall, try herbs. "There are many herbs that are drought-resistant and make great additions to a wall, such as creeping thyme, silver thyme, English lavender, trailing rosemary and such cooking herbs as mint, marjoram, sage and sweet basil," says Anne Roth, a landscape designer with Roger's Gardens in Corona del Mar. You may also want to try parsley and santolina.
To ensure a little color in your landscape, there are a variety of low-water requirement flowering plants from which to choose, including Mexican primrose, coral bells, lamb's ears, blue or white salvia, coreopsis, fibrous begonias and geranium sanguineum.