The Best Return on a Landscape Isn’t the Food It Grows

For most builders, the landscape is what goes in after the building: a lawn, some shrubs, a tree if the lot allows. Studio Viridian wants the reverse. Its Nature theme commits the firm to design buildings and their living landscapes together, with equal care, so that each restores the other. Its growing arm, Viridian_grows, began in December 2025 as a separate operation. It is now part of the studio, and in time the firm means to hire a director of landscape architecture every bit as skilled as its building architect.

The working paper Common Ground asks which landscape and growing investments return the most good per dollar, and where they meet what landscape architecture’s top international honor, the Cornelia Hahn Oberlander Prize, has recognized. As in the firm’s Pritzker paper, Impact by Design, the prize is kept out of the score, so the work that photographs well can’t crowd out the work that does the most good.

No nature investment reaches the top of the firm’s impact scale, where the paper on all six themes puts family homes for voucher families and lead-safe homes for children. Nature’s strength is breadth at low cost: 13 of the 19 ranked investments take little money or effort, and most can share one site visit, one survey and one maintenance plan. The three highest returns are keeping big trees, testing and rebuilding the soil, and helping shape the city’s rules. None of the three matches the prize’s strongest drivers.

What the prize honors

The Cultural Landscape Foundation established the prize in 2019 and first awarded it in 2021. It goes every two years to a living person, collaborative or team with a significant body of built landscape work, and it carries $100,000 and two years of lectures, tours and publication. Julie Bargmann won first, in 2021, for turning poisoned industrial ground into public parks. Kongjian Yu won in 2023; his “sponge city” parks, which absorb, clean and store floodwater, became national policy in China, and he died in a plane crash in Brazil in September 2025. Mario Schjetnan and his Mexico City firm, Grupo de Diseño Urbano, won in 2025, praised by the jury as “a strong voice for social engagement and environmental justice.”

Cultural memory leads, which suits a prize run by a foundation for cultural landscapes. Then come water made visible, native ecology, public access and landscapes designed with their buildings. Food barely registers. Two of the twelve works turn on it, and both are agrarian heritage: Yu’s campus built around a working rice paddy and the canals and chinampa fields of Xochimilco. Every laureate is honored for public landscapes that anyone can enter, so a portfolio of private rental lots, however good, would not on its own be the body of work a landscape jury weighs.

Oberlander herself, who practiced from Vancouver from 1953 until her death at 99, worked almost always beside architects. She made the roof garden of Robson Square with Arthur Erickson and the green roof of the VanDusen Botanical Garden Visitor Centre with Perkins+Will. It is the way Studio Viridian intends to work.

A mission that holds up in part

The December 2025 plan gave Viridian_grows five aims and a method: energy-efficient, year-round cultivation of food and botanicals. The paper tests each against the evidence and proposes a sixth aim.

Why food doesn’t pay back as food

A 2024 study of 73 urban farms and gardens found that urban-grown food averaged about six times the carbon per serving of conventional farming. Most of it came from the beds, sheds and paths themselves. Indoor farms fared worse. Plenty filed for bankruptcy in 2025 after raising close to a billion dollars, following AeroFarms, AppHarvest and Bowery, and Singapore dropped its “30 by 30” goal for local food in November 2025.

For food security, money works better than growing area. In a lottery-based study of Seattle’s Fresh Bucks program, $40 a month for produce raised household food security by about 31 percent, and the gains reversed when the benefit ended. So the paper recommends meeting the Living Building Challenge’s urban agriculture rule on most Seattle sites through its second pathway: a smaller growing area plus a farm share delivered to every building each week, subsidized for lower-income residents.

Gardens still belong in the work, for the people who tend them. In the first randomized trial of community gardening, in Denver, gardeners ate more fiber, were more active and reported less stress and anxiety than people who kept waiting. Seattle’s P-Patch program had 1,685 people waiting for a plot at the end of 2023. The paper proposes a bed for every household that wants one, on soil tested first, with the firm maintaining the bones so the garden works even when nobody in the building is an enthusiast.

The best returns are in the trees, the soil and the water

Daytime summer air cools most where tree canopy covers more than about 40 percent of a city block. A model of 93 European cities estimated that 30 percent tree cover would have prevented about a third of the deaths attributed to urban heat in the summer of 2015. Seattle’s canopy has been slipping, and almost half of it grows in the Neighborhood Residential zones where the firm builds. A large tree takes fifty years or more to replace, so within the firm’s holding horizon a kept tree can’t be matched by planting.

Soil comes next. Old paint and decades of leaded gasoline left lead in city yards, and children swallow soil as they play. Testing a lot costs a few hundred dollars and decides where play areas and food beds can safely go. The paper flags the EPA’s 2024 screening levels for residential soil for confirmation. Water is the third. A chemical formed from tire wear, 6PPD-quinone, washes off roads and kills coho returning to urban creeks, and filtering the same runoff through bioretention soil prevented the deaths in tests. Seattle’s RainWise program rebates most or all of the cost of rain gardens and cisterns in eligible basins.

Where the work meets the prize

Set the prize’s drivers against the mission’s aims, and rank each overlap by the impact of the investments behind it.

The three highest-impact overlaps carry only some prize weight. The prize honors repaired ground and changed policy through Bargmann and Yu, but at the scale of mines and nations; at Viridian’s scale they are a soil test and a bonus written into the code. Four overlaps line up: water made visible, public landscape, native ecology and landscape designed with the building. Green roofs show the tension. They were Oberlander’s signature, yet two in Portland held only about 23 and 33 percent of a year’s rain, and much less in the wet winter months. On a small Seattle building, a roof garden earns its place as the residents’ outdoor room.

Eight ideas that fail

The paper also lists ideas that look like impact, and often feature in green building and urban farming, but fail once their full effects are counted.

Building the role in that order

The draft job description for the landscape director needs no new duties, only a new order. The first hire, as the firm’s studio plan already proposes, should be a horticulturist or ecologist. Until the body of work justifies a director, the firm can do what Perkins+Will did at VanDusen and work beside an outside landscape architect on its public projects.

Together the strongest overlaps suggest one recognizable body of work: Seattle’s missing middle, set in kept canopy and sponge lots on repaired soil, with native edges, shared gardens and places for children to play, and joined every year or two by a public landscape on the city’s creeks and schoolyards. The paper’s rule for keeping it honest is the one from Impact by Design: let impact decide the money, and let the prize decide only the design time. Schjetnan’s firm was nearly fifty years old when it won.