March Web Exclusive

Vertical Edible Walls

        by J.F. Pirro

        It began with lettuces and then herbs in his backyard, and then George Irwin's family had the idea of trying to grow tomatoes, cucumbers and lettuce in the same vertical panel. That experiment may mark a revolutionary approach to agriculture. At the very least, it's innovation.

        When it worked, the initial reaction--You're growing what on the side of a wall?--was predictable, Irwin says. "To me, it was the new garden. Since then, we have been producing an ungodly amount of food," he adds.

        A longtime industry leader in green roofs and walls, growing food was a logical next step for Irwin's Green Living Technologies International (GLTi), which is now taking advantage of patented growing strategies to provide an abundance of options for vertical agriculture through GLTi Food Factories and patented Edible Wall Technology.

        Based outside Rochester, N.Y., the company has an interest in education and is helping to pioneer the concept of "zero miles" from farm to table with its indoor and outdoor edible walls that promote the growth of fresh fruits and vegetables, particularly in urban environments. GLTi's Mobile Edible Wall Units, essentially A-frame walls on wheels, work in parking lots, backyards, vacant lots, buildings or other enclosed areas--without the need to build raised beds or break ground.

        When you grow up a wall, plants grow out with hardly any wastewater, notes Irwin, GLTi's president and founder, while debunking the myth that he's growing hydroponically. While that approach exists, it's too high-risk, he says.

        "Our cells can go five days without water and be fine," Irwin explains. "So many have the concept that it's still a horizontal level, but we're truly growing vertically. We can take the same floor space and at least triple the growing capacity."

        Vegetables can be grown on both sides of a typical A-frame unit, which measures 7 feet high by 4 feet wide, though they come in various sizes. GLTi's growing media is a compost-peat moss mix, GLTi Green Wall bioSoil, which Irwin uses for all his green wall and roof projects. He promises that heirloom tomatoes grown in January taste the same as those grown in August.

        He says the system offers tremendous advantages: year-round production, reduced water usage, reduced or no fertilizer, and increased yields and production in less space. It's a viable proposition, and there are various economic benefits, including the ability to benefit from the marketing and publicity associated with such a unique growing venture. Plus, a high-quality harvest should attract the interest of high-end restaurants, grocery stores and farmers' markets. From that type of clientele, growers should be able to command a higher price for their produce.

        "For a commercial grower, it's all about producing and producing, but it's also about quality," Irwin says. Existing growers can use his products to help streamline operations or simply as add-ons.

Vertical Wall Potato Harvest

        Growers can also practice succession planting, and at 30 days, for example, put seed in next to a growing plant, overlapping growing, sharing space and producing high-intensity yields. Though it can stress the growing media, particularly with tomatoes, you still only need to change the growing media twice a year.

        Two irrigation options complete the easy-to-use vertical farms: Manual irrigation is accomplished by adding water to the drip reservoir at the top of the unit; optional metered and automatic irrigation is available for larger commercial growers.

        Thus far, however, he says commercial growers have only been "kicking the tires." If they're truly interested, then they need to buck up, fly him in to spend two days, and "if it's the right fit, fine," Irwin says. "For the price of a plane ticket, they will have my full attention."

        Though there are obvious up-front costs, the cells are made of high-grade aluminum stock and the panels are manufactured from food-grade stainless steel to ensure longevity and safety in growing food. The equipment becomes a one-time investment that Irwin says will last forever. Even after three years, there's never another time a grower will have to buy growing media if it's properly composted, recycled and reused. "In 12 to 18 months, you will have a return on your investment," he promises.

        Early applications
        GLTi's first commercial project was in the infamous Skid Row in Los Angeles. For the project, GLTi teamed up with several nonprofit agencies to help feed the homeless. Irwin created a series of edible walls and trained local residents (some jobless) to plant, nurture and harvest the walls, which covered 720 square feet of growing space. The development led to bigger and more productive layouts beyond the initial outlay of 180 self-irrigating, lattice-like panels.

        Irwin had installers on the job, but he ended up sending them home and taught the homeless how to grow vertically. "They had the most interest in the project," Irwin notes.

        Since education remains a top focal point of Irwin's interest (he's a former schoolteacher), he also teamed with his friend Stephen Ritz, a teacher at Discovery High School in the Bronx, N.Y. Ritz's students have consistently made national news with their project-based Mobile Edible Walls and the food they're growing in classrooms. Irwin recalls, "After the first 45 minutes I was there, he said, 'I have no idea what you're doing, or how you're doing it, but these kids don't sit still for anyone.'"

        The Mobile Edible Wall Unit is now available with a 200-page unit plan for instruction, including rubrics, assessments and core crossover that adhere to the national learning standards. "What we have is a tool to engage kids," Irwin says.

        Ritz brought that first batch of kids to a conference in Boston (along with Irwin, who helped fund the experience), and they installed an edible wall. Those students became the first high school graduating class in Ritz's unique program that produces what he calls "green graffiti." Some became certified installers for GLTi that first summer.

        The Food Factory is another not-so-pie-in-the-sky Irwin concept. The idea and application are simple: Expand the farm from one single self-use panel or even Mobile Edible Walls to several panels and the commercial A-frame. Expansion could theoretically encompass hundreds of thousands of vertical growing units.

        A Food Factory is an indoor farm that operates on a pick-your-own basis year-round, utilizing an indoor anaerobic digester and worm composting along with GLTi's vertical edible walls. It maximizes production space to include walls, roof and vertical floor plans, using existing buildings retrofitted to grow food. They can be seasonally expanded to parking areas, exterior walls and rooftops, offering community jobs, hands-on education, rehabilitation, research opportunities and training.

Patented Edible Mobile Wall

        Irwin hasn't yet become a venture capitalist and sought out seed money. He says it would have to be the right relationship, and with a partner who values education as much as he does.

        Harvesting in Philadelphia
        Angela and Michael Bucci's Philly Green Wall, an architectural design-build firm, first began experimenting with installing green roofs in conjunction with Irwin. They worked together on the PNC Bank Pittsburgh project. At the time, it was the largest green wall installation in North America, covering some 120 feet up the side of the building.

        "What we do is nice to look at," Angela says. "A green wall is decorative and has health and environmental benefits. People are happier around green growth, but growing food is powerful. When you start growing your own food, you realize what food is supposed to taste like."

        At the couple's renovated home/office/warehouse there is about 2,500 square feet of green roof space, with about 500 of that in vegetable production. Plans are to double the vegetable production this growing season. The couple is experimenting with Irwin's panels, and they have found that lettuce grows well in 3-inch panels, while carrots and celery do better in 6-inch panels.

        They're using a single-sided 4-by-2-foot A-frame, an 8-by-4-foot vertical interior greenhouse wall, a 4-by-12-foot outside green wall that's a combination of decorative plantings and herbs, and two 6-by-5-foot walls on the east side of the building off a catwalk above the second floor overhang, as well as space on the roofs and cold frames on the roofs.

        "It's like one big field, and when creating a paved deck area we really want to utilize the perimeter space," Michael says. "We can grow an enormous amount of food in just those little surrounding strips."

        Angela says that edible green wall growth in the Northeast is challenging with the winter weather, but the couple has found that perennial lettuce like radicchio will regenerate itself, as well as parsley and even some tomatoes. "It's been exciting for us even to see what regenerates itself without having to plant again," Michael says. "We're finding what we can grow." They've also discovered some things they can't grow, like bok choy, which attracted pests.

        An edible green wall takes more to maintain than their typical green walls. "It's almost a daily operation," Michael says.

        What they don't eat of their harvest, they either give away or find a creative use for, like making ketchup from cherry tomatoes. The couple also knows that their produce could someday be sold at farmers' markets or to restaurants. Angela says, "There's a market. In looking to the future, we know that if we can grow more, we could sell it."

        For now, as designers, innovators and installers, they have a model to showcase to potential clients who want to have an edible rooftop or vertical farm wall. They believe the future economy will demand more immediate, on-site food production. They say education is the key.

        The concept could work in townhome or condominium developments, where common areas are already shared and paid for with association fees. "It's a realistic vision," Michael says. "You could have a green wall gardening committee. In any group you'll find those who like growing things."

Food Chain: Send-Off from Cal Poly

        The author has been published in national and regional magazines as well as daily and weekly alternative city newspapers. A gentleman farmer in Quakertown, Pa., he writes about people, social trends, historic preservation and 18th-century America, agrarian culture, land use, and sports and recreation topics.

        Photos courtesy of George Irwin.