Wildflower is published quarterly by the Wildflower Center. Its content is national in scope with articles about the conservation and use of native plants as well as news from the Wildflower Center. A subscription is provided to Wildflower Center members as a benefit of membership.
By Nan Booth Simpson
Imagine that Mayas had ventured up into Texas around 900 A.D. and built temples on a bluff over the Colorado River just west of present-day Austin. The site was abandoned, of course, and dense vegetation had obscured the buildings...
This was the premise presented to Austin landscape designer/contractor Richard D. Fadal and landscape architect Jon van Allen when they first visited clients who were building a home based on classic Mayan art and architecture. The challenge was to create a garden that gives the appearance of a tangle of trees, vines and understory plants that had grown undisturbed for more than a millennium.
When the project began, the terrain was stark. Because road construction companies and utility companies had used the location as a staging area, little remained of the natural landscape. Still, the stunning views captivated the homeowners. While their romantic "history" generated an intriguing concept, the designers' understanding of the region's real (and far older) geological and ecological history enabled them to re-create a Hill Country environment "from the ground up." For millions of years this land had been the bottom of a shallow sea. As the fossil remains of sea creatures hardened into deep limestone formations, ancient mountains and volcanoes arose, only to be weathered and worn down by rivers and streams.
Many of the plants native to the Texas Hill Country can be found nowhere else on earth. A surprising number of its trees and shrubs are evergreen; escarpment live oaks (Quercus fusiformis) and the misnamed cedars (Juniperus ashei) are abundant. This rich palette of plants and naturally occurring rock for paths and walls make garden design in the region particularly interesting, provided that the designer respects the limitations of the soil, sporadic rainfall and harsh climatic extremes.
The house had been under construction for three years before landscape designers were called into the process. Its central two-story section is flanked by two angled wings - each meant to evoke ancient, excavated buildings. This expansive U-shaped structure had been sited near the highest point of the property at the base of a ridgeline, facing southwest across a plateau that abruptly drops some 500 feet to Lake Austin. While the steep slope remained relatively undisturbed, the two-acre plateau that was slated to become a garden stood barren.
Fadal understood that restoration on this stark, windy hilltop could only be accomplished by emulating the work of nature. New soil had to be formulated and land totally reshaped before any planting design could even be considered. "I also knew that a garden that lived up to William and Bettye Nowlin's vision would have to transcend the ages, creating a sense of belonging and bridging many plant species," says Fadal.
"With their keen interest in architecture and astronomy, the Nowlins wanted the design to reflect the mystic nature of the house. As I explored various ideas with the architects and clients over a period of months, several gardens-within-the-garden began to take shape. I proposed plazas and elevation changes to add interest and focus on special views of the lake and the house." The final design includes a multiplicity of interconnected spaces, transition zones and even secret passageways.
"The Nowlins needed thick plantings to ensure privacy from the growing cityscape. To tie into the existing terrain and provide total seclusion, Fadal extended the natural ridgeline on the east side of the property around the north and west sides, utilizing site rubble that included excavated caliche and the masons' chippings and broken stone. Today the house is hidden from the street behind a very plausible-looking 12-foot-high ridge covered with native and hardy adapted plants.
The main entrance leads into a motor court at the rear of the house between two stone-encircled mounds that recall early pyramids of Mesoamerica. The larger of the two mounds obscures the single-story north wing of the house and ties into its roof garden. Planted on these stepped concentric circles are masses of Texas mountain laurel (Sophora secundiflora), wax myrtle (Morella cerifera), aromatic sumac (Rhus aromatica) and yaupon holly (Ilex vomitoria). "The most Mayan of the spaces is the ‘hidden building' that emerges from the landscape," says Bettye Nowlin. "The idea was to create the sense of an ongoing excavation by surrounding the north wing with dense landscaping."
From the entry garden, a limestone block path leads visitors into an open foyer from which they must turn left and traverse a covered colonnade to reach the front door. From this vantage point (the first of many designed into the house), visitors are treated to a panoramic view of the landscape - a central courtyard, terraced lawn and, beyond, the steep, heavily wooded slope down to the lake.
The garden is designed to reveal its mysteries slowly. There are three points of access: from the arcade via a somewhat hidden stone staircase, through the house from its lower level or down a "jungle trail" near the entry gate. A large oval courtyard hugs the southwest-facing façade of the house, accented with three large Texas sabal palms (Sabal mexicana). "We wanted to use hardy plants native to Texas whenever possible, including the palm trees, which are also common in Central America," says Bettye Nowlin. "We felt these were important to the overall look of the site. The palms are even a central theme in the dining room, connecting the inside to the outside." The courtyard's other plantings soften, but never obscure, the home's handcrafted, unmortared limestone block walls and handsome turtle-themed friezes.
On a terrace level below this central courtyard, the landscape opens up to include a "Solar Courtyard" where the rays of the setting sun pass through three pairs of overscale granite columns to mark the winter solstice, equinox and summer solstice. Beside this courtyard is a waterfall that spills down to a sleek swimming pool with a gracefully curved disappearing edge. Beside the pool is a comfortable covered seating area with a huge stone fireplace.
Then, a tranquil reflecting pond and stone steps lead down to the next terrace level where a radiating "Celestial Garden" is planted in succulents and colorful native perennials. Here, another waterfall spills over the disappearing edge of the swimming pool into a cozy spa. Beyond this little garden, the land opens into an arc of sweeping lawn, which also serves as a septic field. Across the grass and past the granite columns, one encounters a semi-circular "Sculpture Garden" that serves as a transition level between the house and lawn. From the sculpture garden, the densely wooded jungle trail provides access to the roof garden and back to the motor court.
"Having built the house with a Mayan inspiration, the design of the landscape was crucial to the completion of the site," says Bettye Nowlin. "And like the house, it was a lot harder to get it right than we ever dreamed. The most important aspect of the project was to enhance the house without making everything look surreal. Even though we don't have acres and acres, it feels like we do. Living in the house has proven to be an enriching experience, and the gardens are a big part of living here."
Five years after it was planted, the site needs neither pesticides nor chemical fertilizers to sustain its native and hardy adapted trees, shrubs and wildflowers. Irrigation water is pumped from the lake below. The imported soil is a blend of native topsoil retrieved from roadway and construction sites and blended with composted cow manure from The Natural Gardener in Austin. (In some planting areas, green sand was added to improve drainage.) All of the stone excavated from the site and leftover from the house construction has been incorporated into the design.
The garden beautifully complements the architecture of the house and the personality of the Hill Country. Moreover, it seeks to employ sustainable principles wherever possible.
Fadal draws upon his experience here to advise other homeowners seeking a more sustainable backdrop for their native plantings. "Take a hard look at the design of your property. If you're building a house, insist on retaining as much natural vegetation as possible. Protect existing plants during construction," he says. "If you have an established landscape, look for places where you might add native trees for shade and native shrubs as privacy screens. Consider replacing unused portions of lawns with native ground covers and wildflower meadows for color."
Fadal recommends that gardeners be willing to transplant anything that doesn't work in its present location and discard all invasive plants. He says that where native plant and animal communities have been disturbed, introduced species muscle in and threaten nature's balance.
"Pick the right [native] plants. Select the least water-demanding turf grass available for your region," says Fadal. "Consider slope, exposure and soil type in your choice of plant materials. Prefer drought-tolerant species to more thirsty plants. Then group together the plants with similar needs."
Watering efficiently is also essential. If you are hand watering, Fadal recommends using a soil probe and watering only when the top two to three inches are dry. Water early in the morning to minimize evaporation. Establish watering priorities and zone an irrigation system to the needs of the plants. Irrigate with the lowest possible volume to minimize run-off, while working to obtain the right amount of precipitation for your area.
"Finally, maintain the garden," says Fadal. "Top-dress the lawn with compost and raise the height of the lawn mower. Prune judiciously to maintain the natural shape of the plants. Use organic fertilizers in quantities sufficient to keep plants healthy but not to encourage rapid growth. Remove weeds as soon as they appear to minimize competition for water."
While many homeowners might argue that "sustainable garden" is an oxymoron, their apprehension is well-founded only if the term is interpreted as a garden that can be kept attractive without human intervention. "Where the human hand is involved, sustainability comes with good soil preparation, matching plants to the environment and keeping vigilant against the encroachment of weeds," Fadal explains.
Visualizing a site that had been untouched since pre-Columbian times has provided Fadal a new sense of urgency about how we should manage the land.
"In the 30 years since I began practice here, we are nowhere near the natural beauty that was once Austin's close-in Hill Country. This project has inspired me to redouble my efforts."