Adrian Higgins - Working Toward Guidelines for a Truly Green Garden
There's someone on my block pouring greenhouse gases into the atmosphere, contributing to summer smog and allowing polluted runoff to reach the Chesapeake Bay. It's me. Oh, and you. And everyone else.
The ecological pendulum has swung somewhat since the postwar decades, when homeowners blithely burned autumn leaves and applied nasty pesticides and too many synthetic fertilizers to their garden plants. But we still have a long way to go before our gardens are ecologically sustainable. This may sound strange, given that the whole point of gardening is to venerate nature, secure in the knowledge that our plants trap carbon, provide shade and pump oxygen into the air.
But in existing properties, too many gardens are part of the problem, with plants needing chemical support because they are ill-chosen or in poor soils, or both. Lawns, apart from requiring repeated fertilizer applications, rely on gas-powered mowers and blowers.
Even gardeners who are dutifully trying to be green by minimizing the lawn, turning to hand tools and planting low-maintenance vegetation see storm water gushing down the driveway into the street, losing water that otherwise could be used in the garden while reducing river pollution.
"Our landscapes use a tremendous amount of water without us taking consideration if that resource may be limited," said Heather Venhaus, a landscape architect in Austin.
Venhaus is the project manager of a quietly evolving effort to transform the way we build or redo our yards. The Sustainable Sites Initiative (http:/
The landscape initiative has been developed by the Lady Bird Johnson Wildflower Center, part of the University of Texas at Austin, and two Washington-based organizations, the American Society of Landscape Architects and the U.S. Botanic Garden. Working with volunteer experts, the initiative's staff is preparing guidelines and technical benchmarks that professionals would use to design, build and maintain greener landscapes.
These include using recycled rain and household water for irrigation, improving soil health with compost, choosing plants suited to the site and its climate, avoiding chemicals that contribute to smog and using vegetation to reduce the heat island effect of cities.
The enterprise's Web site features case studies of how an ecologically sustainable garden might be built, including two on the West Coast, where water shortages are an issue and the lush, green front lawn is no longer the suburban icon it once was.
In the Southern California city of Santa Monica, landscape designer Susanne Jett took two 1940s houses on the same street and, as a demonstration project, installed in one a traditional front garden, with all its demands on the environment, and in the other a garden that seeks to tread gently on the Earth.
The Native Garden, installed for $16,700, includes California shrubs, perennials and grasses on a site with drip irrigation and elements to capture and reuse rainwater. Jett installed roof gutters and a rain chain to direct rainwater to a catch basin, which then moves the water to a buried pit in the opposite corner of the yard. The infiltration pit, measuring four cubic feet, is filled with plastic cells but could contain four-inch stones. The water stored in it after a storm seeps into the soil to feed the deep-rooted, drought-tolerant plants in the garden, and none of the rainwater leaves the site.
The Traditional Garden, installed for $12,400, features such typical but inappropriate plants as azaleas and gardenias that like heavy soil on the acidic side, planted in sandy, alkaline soils, along with hydrangeas and fuchsias. It also has a lawn and sprinklers.
Jett calculated that the Traditional Garden consumes more than 280,000 gallons of water per year, generates 647 pounds of yard waste and costs $223 annually for the labor to maintain it, including mowing and edging the lawn.
The Native Garden is simply cut back by hand twice a year, consumes 64,000 gallons of water, generates 219 pounds of yard waste and costs $70.44 to maintain annually.
"People are attached to the lawn, but it's a landscape paradigm that's in the process of changing," said Jett, owner of Jettscapes Landscape.
In Portland, Ore., landscape designer Deborah Tolman created an eco-friendly garden for Betsy Malolepsy and Gary Battershell. To avoid soil compaction, no heavy equipment was allowed on the site, and the pesticide-contaminated soil was amended heavily with compost. Rain barrels collect water, plants were selected for their own microclimates and tap-water use for the garden has been reduced to just 10 percent of household consumption, even though the couple has a garden that supplies 60 percent of their vegetables.
"It was key to me to have the garden look good," Tolman said. "There are some vegetable plantings in the front yard; you just can't tell."
The initiative's guide is being developed for engineers and landscape architects and "is too technical for homeowners," said Holly Shimizu, executive director of the Botanic Garden. She hopes for a version for homeowners "so they can do it themselves or know what to ask" of a professional.
However, it often takes finding the right professional to make it work. Tolman not only designed the garden for Malolepsy and Battershell but also allowed them to do much of the labor themselves to save money and then taught them how to maintain it in an ecologically sensitive way. This is not the business strategy of a lot of garden design firms.
"I was able to copy the practices that Debbie taught us," Malolepsy said. "We definitely didn't want to use pesticides; we wanted to grow food as much as we could and have little enough grass that we can use a push mower," she said.
They recycled chimney bricks into paving, started composting to build the soil and turned a fallen tree into firewood and fencing. Salvaging old material is one of the tenets of the Sustainable Sites Initiative.
Jett anticipates a time when jurisdictions will exert controls similar to those in Santa Monica, where site runoff and the use of pesticides are not allowed. Soon, a state law will require future irrigation systems to be linked to weather conditions via satellite to reduce water use.
"I have seen a huge increase in homeowner interest and by landscape professionals," Jett said. "They are realizing this is the way of the future. There's still a lot of resistance from homeowners and professionals, but it's going to come around. Unfortunately, [a lot of people] will be forced into this, and they won't be prepared."