Heights of Fancy
Writer: Mary Vinnedge
Green walls—beneficial in many surprising ways—bring a dramatic dimension to indoor and outdoor gardening
Why grow your garden up instead of out? “It’s the wow factor,” says Denise Eichmann, senior project manager for Ambius, a company that designs and maintains plantings in business environments around the world. “People are drawn to the wall inside a hotel we did in Chicago. They want to have their picture taken in front of it.”
“It’s a living piece of artwork,” agrees Mike Coraggio, founder and CEO of Bordentown-based vertical-garden company EcoWalls.
Yet a green wall isn’t just another pretty space; it appeals to other senses too. People love to touch the foliage, Eichmann says. Exotic tropical plants such as bromeliads (common in indoor vertical gardens), for example, beg for a tactile reality-check.
Green walls (a.k.a. vertical gardens and wall gardens) also reward your senses of smell and hearing, Coraggio says. Queen anthurium and Epiphyllum cactus are fragrant in the evening; ‘Sharry Baby’ Oncidium orchid blooms have a chocolate scent. And while the plantings prevent echoes in rooms with hard surfaces, the trickling of irrigation a few times each day sounds like a fountain. (If you dislike the faint gurgling, the system can be installed to ensure silence, he notes.)
But wait: There’s more! The plants can be irrigated with graywater, purifying it in the process, and they clear the air of noxious gases emitted by building materials, paints and furnishings. In addition, the leaf space of 50 square feet of vertical garden “provides oxygen equivalent to a 14-foot tree,” Eichmann says. She adds that some cities require that a certain amount of landscaping be set aside with any building project, and vertical gardens satisfy the requirements within a small footprint. (That small footprint also makes them attractive for condo balconies, townhomes with minimal to no yards, and to lend grandeur to modest entryways.)
Another plus: Wall gardens buffer temperatures, reducing heating and cooling needs.
Because of these benefits—and because they can be assembled using recycled materials, such as plastics in recirculating tanks—vertical gardens assist in LEED (Leadership in Energy and Environmental Design) certification for projects. Some municipalities (Philadelphia is one) offer incentives for green walls, Coraggio says.
Finally, vertical gardens encourage people to commune with nature, a known stress-defuser. And if these wall gardens aren’t too tall, they’re a godsend for people with limited mobility—perhaps because arthritis makes bending difficult or because they must garden from a wheelchair.
What You Need to Know
Now that you’re thinking you want a wall garden, here are some key considerations.
PLANTS Vertical gardens can thrive in any exposure indoors and out if you choose the right plants for the right setting; we list a few options here. Pothos and philodendron need little light indoors (Eichmann calls them “closet plants”). Bromeliads, orchids, anthuriums, ferns, spathiphyllum (peace lily) and tradescantias (commonly called wandering Jew) grow in brighter indoor light. For outdoor gardens that keep their foliage intact year round, Eichman recommends broadleaf evergreens such as Juniperus procumbens, cotoneaster, Euonymus coloratus and microphyllus. (Consult the USDA map for cold-hardiness zones at planthardiness.ars.usda.gov/ PHZMWeb to guide choices for outdoor plantings; much of New Jersey is Zone 7, reaching lows of zero to 10 degrees Fahrenheit). Coraggio’s outdoor choices include heuchera, hellebores and vinca (periwinkle). Annuals can be added during warmer weather.
LIGHTING If indoor light is dim, small skylights (Solatube is one brand; Sun Tunnel by Velux is another)—no electricity needed—can sometimes raise levels enough. If that’s not enough, add artificial lighting tailored to the ideal wavelengths for the plants, Coraggio says. Metal halide architectural lighting is one option; for small living walls, energy-efficient LED lights may be adequate. Sometimes there’s quite a challenge in balancing plant needs with human comfort. “In a restaurant’s culinary garden, for example, you want subdued lighting for ambience, but the plants need bright lights to grow,” says Coraggio, whose company has succeeded with basil, thyme, mint, chives, strawberries and leafy greens such as lettuce and Swiss chard growing in glare-free settings.
GROWING SYSTEMS Wall gardens often use hydroponic processes that cultivate plants in nutrient solutions rather than soil. These systems include a rugged inorganic growing medium that anchors the plants (even when newly planted) within a paneled system affixed to walls or on a paneled, freestanding and even mobile “wall.” Soil-based systems exist too, but soil can erode, and plants typically have to be grown horizontally for a few weeks to grasp the soil well before they are shifted upright.
WEIGHT Can your wall support a vertical garden? Eichmann says you should consult a structural engineer to be sure. Hydroponic systems can weigh as little as 10 pounds per square foot compared with soil’s 45 to 50 pounds.
ELECTRICITY AND WATER A power source will run the timer-controlled feeding/irrigation equipment and (if required) supplemental lighting. You’ll need to tap into a water supply, whether potable or graywater. Depending on your system, Coraggio says, water can be recirculated, passing through the wall panels, growing medium and plant roots, and then the excess—cleansed by the plants—is collected for redistribution. Non-recirculating systems convey runoff into wastewater or recycle it for irrigation.
COST EcoWalls cost roughly $90 per square foot for the system alone; with plants, labor and installation, the price reaches about $135 per square foot. Ambius, which does only commercial installations, says its hydroponic systems range from about $150 to $200 per square foot installed, with bigger walls having a lower per-square-foot cost because you can use one large irrigation controller to operate the entire system of multiple irrigation zones, Eichmann says.
MAINTENANCE Most vertical gardens need a little more maintenance than horizontal plantings. Ambius requires a one-year maintenance contract (about $15 per square foot per year) with new wall gardens. “The irrigation has to be fine-tuned. For seven days, we’re there every day. The next week, every other day,” gradually tapering off to every other week. EcoWalls offers maintenance services as well as training to homeowners and to independent contractors. Maintenance includes pruning and pinching back plants to keep them in bounds and to encourage bushy growth.
Mary Vinnedge tends an unruly traditional garden north of Dallas-Fort Worth. You may contact her through her websites, WritingGenie.com and EditorForRent.com.
This article first appeared in Design NJ.