Leave Your Lawn for Life on the Urban Farm
A mile or so south of downtown Denver’s growing skyline, gardeners toil under the relentless summer sun, pulling weeds and pruning tomato plants that are thriving now that hail season is over and 90-degree-plus days dominate the forecast. Three months ago, the West Washington Park Community Garden was a brown, barren landscape; today, gardeners are harvesting crops from garlic and onions to kale and beets.
Urban gardeners have no shortage of motivation to grow food: access to fresh vegetables, a chance to interact with nature in a concrete jungle, an excuse to spend time outdoors and take in some of the depression-alleviating microbes that live in soil. Now there’s another reason to replace your green lawn with leafy greens: water conservation.
Vegetable gardens often use less water than many picturesque green lawns—in some cases, half as much, according to gardening and water experts. In Denver, for instance, residents, schools, and water agencies have started installing vegetable gardens to save water. The push to factor water consumption into the decision to replace lawns with urban gardens seems to be strongest in metropolitan Denver, but the potential exists in just about any drought-prone area.
In drought-stricken California, where some water agencies pay residents thousands of dollars to rip up their lawns, some edible plants—artichokes or passion fruit, for example—can qualify as low-water plants that residents can grow instead of drought-resistant decorative vegetation. Urban Plantations, a San Diego company that designs and installs mini-farms, calculated that replacing a lawn with a fruit and vegetable garden will reduce water use by 66 percent.
“Once we put the numbers together and started explaining it to people, we started seeing a lot of interest,” said Mat Roman, Urban Plantations’ office manager. “People want to put in vegetable gardens instead of desertscape, and that’s both current clients and prospective clients. We’ve seen a tremendous increase in business.”
Denver Water, Colorado’s largest water utility, used to promote xeriscaping—replacing lawns with drought-resistant plants—as the optimal water-saving way to landscape a piece of property. Today, though, the agency encourages people to look not just at the amount of water used but at the overall value that that water will provide.
“I think vegetable gardens are a perfect example: You can save water. You can grow food. You can have organic vegetables for your family at the same time,” said Mark Cassalia, water conservation specialist for Denver Water.
“Our years of data from water bills and our partnership with Denver Water has helped us to understand that community gardens use about 40 percent less water than lawns,” said Jessica Romer, director of horticulture at Denver Urban Gardens, a nonprofit that operates a network of community gardens around the city.
In 2010, the group calculated that community gardens used, on average, just over nine gallons of water per square foot each growing season—half of the 18 gallons that Kentucky bluegrass needs. That, however, is still more water than consumed by drought-resistant plants, which use between zero and four gallons per square foot, according to Romer.
Cassalia said he’s seeing more people installing backyard farms in part because they like the idea of growing their own food while reducing water use—and water bills.
“If someone went big and put in an 1,000-square-foot garden, you’re looking at 7,000 gallons saved annually. And we see that all the time,” he said. In urban areas, smaller gardens are usually more common, and the water savings will be less—but 3,500 gallons of water saved at many individual gardens can add up across a city.
Aurora Water, the water agency that serves the city of Aurora, just east of Denver, is also pushing urban farms. After converting large grass plots that the agency owned to vegetable gardens at two sites, the city noted a 74 percent drop in irrigation. The agency also offers a gardening class for residents interested in learning how to grow vegetables.
Cassalia emphasized that gardens aren’t going to be a sensible choice for everyone, but they’re an option that Denver Water is increasingly encouraging and that more people are considering, whether for a residential backyard or an unused lawn at a public school. The agency doesn’t provide financial assistance to convert lawns to gardens, but Cassalia said such incentives are not out of the question in the future.
Denver Public Schools operates about 35 community gardens. The school district doesn’t break down its water consumption by use and doesn’t know if or how much its gardens are saving. But Laurel Mattrey, the district’s sustainability planner, said water savings have influenced decisions to replace lawns with vegetable gardens. “That’s something we look at when we’re planning for our land,” she said. “We certainly encourage xeric landscapes and gardens over turf.”
“We very much welcome gardens on school sites because it’s a use of our land that’s beneficial to the community; it’s a benefit to the students,” she said. “Because otherwise, mostly it just sits there as turf, and we water it.”
This post has been revised to reflect the following correction: An earlier version of this article misstated the water savings from large and small gardens. It was 7,000 gallons saved annually from a 1,000-square-foot garden. A smaller garden would save 3,500 gallons annually.