Tucsonan Michael Ray builds arches to pamper his plants and save water.
Considering our dry climate, the diversity and abundance of food grown here in Baja Arizona is at times astonishing. Even so, because many of these crops require supplemental water, when Tucson retiree Michael Ray became concerned about the amount of water he was using to grow his own food, he set about designing an ingenious solution. It’s called Nurse Tree Arch, and while it looks like a miniature greenhouse, it is, oh, so much more. (Indeed, in the Sonoran Desert, nurse trees often act as shelter for saguaros and other slow-growing plants as they mature.)
Ray has been gardening in Tucson since the ’70s. In addition to challenges such as the poor soil quality, blazing sun, and desiccating winds, he says he’s witnessed the incrementally worsening drought conditions in the region. “Because of warming, we have a smaller spring window,” he said. “Spring has become very unpredictable.”
Undaunted, Ray now designs and constructs modular arch structures that protect his plants from wind and sun, while retaining precious moisture. “I’ve dropped the idea that I need to garden in the sun,” he said, proudly gazing at his tomato vines, still healthy in late January. Golf-ball sized ruby fruits peek out from underneath velvety emerald foliage—a far cry from the withered brown vines that plague many backyard gardeners in Arizona.
Ray’s arches are different from greenhouses because of their many intersecting rectangular panels, which can be removed altogether or tilted inward to allow rain to run in. He uses Luminet, an aluminum covered cloth, to reflect heat and to filter and scatter sunlight. Underneath the soil, he lays perforated pipes, which are hooked up to a fan and circulate moisture. “The roots of plants are very intelligent about water. They’re designed to seek it,” he said. “This system tells the plant’s roots that there’s water down there, so you get deep root growth and much better performance than with a drip irrigation system.”
The arch system has worked remarkably well, and Ray plans to design a kit to market to small-scale urban agriculturists, restaurants, schools, and the like. At the moment, a custom-built arch would run about $5,000, which he knows isn’t within the reach of most backyard gardeners. “Ultimately, I’d like to contract that work out,” he said. “I see myself on the design end of it—but these are meant to be reproduced.”