Walls and fences are typically used to keep people and areas separate, but at the Desert Botanical Garden an unusual series of structures actually brought people together. Wood, concrete, steel, stone and block combined to create a variety of richly textured and highly functional separators that both physically divided and visually connected open spaces.


Low Relief Retaining Wall


The retaining wall between the greenhouse and the South Wash was a functional requirement that could have easily been overlooked as a mere engineering solution. Instead, project architect Matt Salenger, AIA of coLAB Studio and 180 degrees design + build turned the 100-foot concrete wall into a gentle meandering design feature by casting in low-relief vegetation motifs using leaf debris gathered on site by garden volunteers. A rebar guardrail continued the functional effort of separation at eye level, yet was easily transparent to afford views to the wash and beyond. Once washed away, the artfully arranged leaf litter left fossil-like patterns behind, knitting together the manmade and natural worlds.



Placemaking at The Great Wall


The Garden also needed a means to separate the “front of house” from “back of house” operations at the Horticultural Center, while allowing the public some degree of access and understanding of the building’s purpose and innovation. Many less interesting designs languished on the boards until Salenger conceived a Great Wall of boulders and gabions that were not only functional, but gave garden volunteers an opportunity to get involved as well.


Each “toothpick boulder” was selected for its length and character – a full 1/3 of the boulder must be buried underground in order to support its own weight. While each rock was a different height, the tops were aligned by burying the boulders at varying heights, making the end result look much more effortless than it actually was. Over 436 tons of rock were brought down from a quarry in Kingman, and it took three weeks to set the 24 boulders in place.

When the garden staff and construction crew started fondly naming the boulders endearing names like Porkchop, Sputnik, La Lengua and Little Horn, we knew that we’d helped forge a strong connection to place. Tour guides now often point out the boulders by name as well, showing that lore and love of places isn’t just the domain of ancient history; history is happening today and will be enjoyed by future generations. Now the staff secretly calls the Great Wall HortHenge, after the famous Neolithic earthworks of Great Britain.


“I was proud to be able to work on excavation and selection of the boulders, and to determine how to place them. The Garden was open to new ideas and had the patience with us to work it out,” says 180 degrees design + build project manager and architect Dusty Bodrero, AIA. “The Center’s project changed shape many times due to budget fluctuation,” he noted, so rallying garden volunteers helped contain the cost and aligned well with how the garden prefers to maintain its grounds.


Because constructing the entire Great Wall out of massive boulders was going to be cost-prohibitive, space-filling interstitial zones of gabion baskets were lined with rock from the same quarry.  Garden volunteers installed PVC irrigation pockets inside the gabions to create vertical gardens that simulated desert canyon microclimates that native species could happily cling to.



Upcycled Perimeter Fence and Planters


Sustainability was one of the top touchstones of the project. Commercial construction can result in a lot of waste, and the 100-foot wash retaining wall was going to require a lot of wood formwork and stabilizing reinforcements. “If you can’t repurpose the formwork, it all just goes to the landfill. It’s no longer new lumber; it’s discolored, splattered with concrete, and got holes in it,” explains 180 degrees design + build principal John Anderson, AIA.


180 degrees design + build decided to salvage the lumber and give it a new life as a texture along the four-foot courtyard perimeter fence, and to face the demonstration planters in the education center.


An unexpected boon came in the form of free wood. Local corporation Intel provided two truckloads of wooden pallets formerly used to ship electronics. Where some might see landfill, we saw opportunity. Garden volunteers broke the pallets down into boards, then cut them to size for use in the fence and planters. A simple water based sealer has extended the life of the wood, and a steel plate protects the endgrain on top from both moisture and sun exposure. “It’s been two years and it’s holding up really well,” Bodrero reports.



An Agile Design/Build Process


“While Salenger was the design lead, 180 degrees design + build was brought in as a partner to make the project even better,” says Anderson. Because of our grasp of both design and building know-how, the Desert Botanical Garden realized that we’d give the project all the attention it deserved.


At the heart of the process was collaboration. “During the Master Planning stage, we went through a collaborative Integrative Design Process,” says Anderson. “All stakeholders were interviewed, from volunteers to staff to donors and management.  We decided on 18 project touchstones that would help guide how decisions would be made. The welfare of the plants was number one. We used these touchstones as a filter every step of the way. Once you have clear rules to follow everything else falls into place.”


Anderson’s partner James Trahan, AIA, agrees. “We always had a firm vision of where we were headed. When everyone agrees upon the touchstones the decisions come much easier. In anything we do, we might go out on a limb, but it’s going to be thoughtful and well crafted. In the end these projects came out even better than the original plan.”


The challenges of this project were closely tied to budget fluctuation, but weren’t hobbled by it. “The design/build process can be very fluid to help make financial ends meet,” Anderson says. “Commercial construction tends to unfold on a more complex timeline than residential, so having design/build managed by a single firm helps streamline the process. We have a better understanding of the costs, and a command of building technique. Because of that we’re more agile than other firms.” 


Though 180 degrees design + build hadn’t ever constructed anything quite like the Great Wall before, we had a quick grasp of what it was going to take to execute the design and we connected with the right experts to help make it happen, from quarryman to irrigation. “Clients that work with us in the future should know that we don’t take a one size fits all approach,” Trahan says. It all depends on what the project demands, and that’s what keeps us growing.




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