Landscape and photo by Matrix Gardens, matrixgardens.com


Landscape by Outdoor Craftsmen LTD, outdoorcraftsmen.com


Photo courtesy Associated Landscape Contractors of Colorado, alcc.com

Smart zoning helps optimize water use in this garden. Here, delicate roses and aspen grow with low water on the home's shady east side, while more drought-loving plants thrive in the sunny spots. (Landscape and photo by Matrix Gardens, matrixgardens.com)


Though often thick and lush to the point of chaos, xeriscapes can be grown in a crisp, formal design. This “compass” garden is composed mostly of oregano, chives and other herbs, and ornamental grasses. (Landscape and photo by Matrix Gardens, matrixgardens.com )

The Myths and Magic of Xeriscaping

Experts say it's best to weed out misconceptions about xeriscapes before you plant. Here are common mistakes to avoid, along with suggestions on how to create a beautiful water-wise landscape.

by Tyera Eulberg

By now, most Coloradans have heard of xeriscape. In fact, low-water gardens grow throughout Boulder County, in response to ever more apparent climate change and worsening drought. But as the xeric philosophy spreads, so do myths and misunderstanding, leaving many would-be xeriscapers unimpressed and apathetic.

People incorrectly imagine xeriscape as cacti and gravel, landscape experts say, and a huge hassle to install. Done wrong, yes, xeriscape can be an eyesore—not to mention dry, hot and a lot of work. But with a little awareness of the possible pitfalls, your low-water garden will bloom lush and vibrant and require very little upkeep.

Xeri, Not Zero

The most important thing to remember is that xeriscape is designed to use plants, says David Bailey, owner of Urban Oasis Inc., a Lyons-based company specializing in water-efficient landscape design. He often sees gardeners rip out grass, trees and flowers, and cover the whole landscape with fabric and rocks, thinking that they're xeriscaping. “We call it zero-scape,” Bailey says. While indeed there are no plants to water, zero-scaping wastes energy and resources. The rocks collect the sun's heat and radiate it against the house at night, spiking home-cooling needs. Meanwhile, organic matter blows into the rocks and decomposes, creating a very rich soil in which weeds thrive. “It looks like hell,” Bailey says of zero-scape, and requires constant weeding or harsh herbicides, making this landscape a maintenance nightmare.

The lowest-maintenance, lowest-water option is actually a shrub bed, says Alison Peck, founder of Matrix Gardens in Boulder. Native shrubs, like silver sage, Apache plume and three-leaf sumac, require no supplemental water beyond normal rainfall. And, if the beds are designed so that the plants border each other when grown, they leave no room for weeds.

With colorful leaves and tidy growth, native shrubs are a desirable, but often ignored, element of xeriscaping. “Too often when people replace lawns, they put in a bunch of flowers that require lots of care,” Peck says. “My rule of thumb is: nature fills a vacuum. Weeds get into flower beds, but not into full shrub beds.”

Of course, xeriscaping embraces flowers as well, weaving rainbows of wildflowers and drought-resistant annuals. And they needn't be high-maintenance. “If you have a very precise, formal image of the garden in your head, you're going to work your butt off,” Bailey says. For example, “deadheading is a lot of work based on the premise that the flower is beautiful, but the seed isn't. If you change your
perspective, it saves that much effort.”

Quit Coddling

In reality, one of the biggest mistakes both Bailey and Peck see is over-maintenance of xeriscapes. Gardeners pamper their xeric plants with compost and other soil amendments, hoping for better growth. While low-water species may take off initially, they ultimately founder in this inappropriate environment. “Native and adapted xeric plants don't like chocolate-cake soil,” Peck says. “In amended soil, piñon pine will lose its character; rabbitbrush will get floppy and collect aphids.”

And soil amendments encourage some species, like Russian sage, to become invasive. On the other hand, penstemon grown in rich amended soil dies from over-growth within four or five years; in the wild, it can live 30 years.

Similarly, over-watering dooms xeric plants. Gardeners typically use a sprinkler system to coat their yard with enough water to support the “thirstiest” plants. This water is wasted on most xeric plants, and most likely will kill them. Instead, xeriscape landscapers suggest placing plants in zones based on their water needs, and irrigating each zone separately so that every plant receives the proper amount.

Sprinklers also weaken drought-resistant plants, as water penetrates only the topsoil, encouraging plant roots to stay near the surface, leaving the plant unstable and vulnerable to weather. Both Bailey and Peck recommend slow-drip irrigation systems that water more deeply and encourage xeric plants to grow long taproots. In addition to being more resilient, deep-rooted plants need even less water. Run the drip at intervals, from every 10 days to every four weeks to not at all, depending on the zones you design.

Native or Not?

Because Colorado 's local flora includes so many tough low-water species, people commonly believe that xeriscapes must contain all-native gardens. Natives do provide benefits; namely they're adapted to survive our area's extreme microclimates, from heavy snows to baking sun. “But native gardens lend themselves to chaos,” Bailey says, while hybrids are more easily controlled. For example, the yellow yarrow cultivar ‘Moonshine' grows from a bunch, whereas the native common yarrow spreads underground, enabling it to pop up all over the garden.

In addition, some natives are just as thirsty as nonnatives, while many plants hybridized from Africa require no water at all. Indeed, our climate supports many traditional perennials like tulips, irises and even roses, in nonirrigated gardens.

The danger of nonnative xeric plants is that some of them flourish too well. Freed of their indigenous diseases and pests, foreign plants can become invasive, supplanting local species and drastically altering the ecosystem. Bailey warns homeowners to avoid plants like Jupiter's beard, an import that's very difficult to control. “When something goes crazy reproducing in the garden, that's when I get scared, especially if I can't get rid of it,” he says. “Those are the ornamentals that get into open space and cut loose.”

He suggests researching xeriscape plants in advance to ensure they're noninvasive. (See “Foreign Invaders” left for a list of ornamentals known to be invasive in Colorado.)

Be assured, however: Hundreds of sensible native and nonnative xeric plants are available to plant, enabling a xeriscape to echo the surrounding neighborhood landscapes. For example, if you're surrounded by bluegrass, choose other, more water-wise grasses to continue the green swath into your yard. Inorganic elements, like stone walkways and walls, also help xeriscapes blend with neighboring landscapes.

And, if your neighbors typically drown their plot, “line your property lines with plants that need that extra water,” Peck says. “It's also a great area for exotic plants that can survive being partially drowned, like daylilies.”

After your xeriscape is established, you may notice xeric plants popping up in your neighbors' yards, too, Bailey says. “The first xeriscape in an area usually becomes a beacon for others.”

Tyera Eulberg is assistant editor of Boulder County Home & Garden Magazine. After a hard week spent plucking thistles for a friend, she'll do whatever it takes to prevent invasive species from sprouting in her garden.

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