Warren McLaren explores some interesting and vertical methods for designing food production into our urban environments.
In survival parlance it is known as the rule of threes. Roughly speaking, without air you have three minutes to live, without water three days, and without food three weeks.
Odd then, that we continue to bulldoze prime agricultural land near our cities to build more subdivisions.
Until our politicians show planning leadership on the issue of urban sprawl and the general populace buys in, how can enlightened designers, architects, landscapers and homeowners respond to the challenge of providing food to Australia’s burgeoning urban majority?
Down the end of the spectrum reserved for grand schemes, we have science fiction style projects, under the banner of Vertical Farming, Farmscrapers or Sky Farming.
US microbiologist and university academic Dr Dickson Despommier is the lead advocate for this hybrid collaboration of architecture and horticulture. He notes, “… we humans are protected against the elements, yet we subject our food-bearing plants to the rigors of the great outdoors and can do no more than hope for a good weather year." In a land subject to drought, flood and pest attack it does seem strange that our poor old fruit and vegies endure the vagaries of inclement weather, whilst we sit snug in our buildings.
Despommier reckons a 35 storey structure occupying the footprint of just one city block could protect and nurture food crops sufficient to feed 50,000 people.
His notion of vertical farming in the city comes with other sweeteners too, like reduced food miles (The energy consumed to get food from the paddock to the plate of urban dwellers) The Australian Rural Industries Research and Development Corporation in a recent paper, on rooftop farming, figure that “the cost of transport of a $1 supermarket lettuce head is around 40 cents.”
Vertical farming is robustly sold as the answer to questions of food security. The United Nations Food and Agriculture Organisation (FAO) projects that by 2050 the world population will be 9.1 million people, necessitating an increase in food production by 70 per cent.
This food will need to grow somewhere. Although Australia is a big place, only about 6.4 per cent of our land is considered arable, or suitable for growing crops, and the bulk of that land is on our coastal perimeter. Yet, according to the Australian Bureau of Statistics, 85 per cent of us already live within 50km of the coast. In short, we’re munching through our most fertile productive farmland, paving it over with houses, shopping centres and roads.
The Australian Natural Resources Atlas notes that most of our soils are ancient and infertile. Andrew Campbell, author of the 2008 policy discussion paper, ‘Managing Australia's Soils’, puts it more bluntly: “Weathered and leached over aeons on this ancient continent, many Australian soils are effectively non-renewable.”
Against such a gloomy backdrop vertical farming appears to be a beacon pointing to the future of food production.
Remember though, vertical farming, as envisaged by Dr Dickson Despommier, is still an untested concept. His skyfarms, rely on hydroponics to grow vegetables. But at what cost?
The aforementioned Andrew Campbell references a FAO paper which found that “the construction of a modern hydroponic system is around $US850,000 per hectare.”
That’s only for plant support and nutrients. Plants also need light to grow. Getting natural light into all spaces of a 30 storey building is no easy matter, to which many an architect can attest.
In evaluating the merits of vertical farming, British journalist George Monbiot cites figures indicating the cost of lighting alone to grow the 500 grams of wheat to bake one loaf of bread would cost just shy of 16 dollars. The same quantity of sun grown wheat is currently worth around 10 cents at the farm gate.
Germany’s Spiegel newspaper offers up similar figures from the Land Institute’s Stan Cox, noting that, “to replace all of the wheat cultivation in the US for an entire year using vertical farming, you would need eight times the amount of electricity generated by all the power plants in the US over a single year - and that's just for powering the lighting.”
Easy then to see why Despommier’s vision of a farmscraper is calculated to cost over $200,000 million to create.
Some designs, like those of Australian Oliver Foster of O Design, propose innovative light wells to bounce natural light into such a building’s interior. Such creative solutions will be necessary if vertical farms are ever to see the light of day.
While 30 storey vertical farm buildings might be a tad ‘rye’ in the sky at this time, there are plenty of much less grandiose projects merging food with our urban landscape.
Like the much more modest three storey government experimental vertical farm in Suwon, South Korea which uses highly energy efficient coloured LED lighting, the wavelength of which they adjust to attain maximum growing conditions.
The Korean government has invested about $3.5 million in vertical farming technology, planning to create 30,000 jobs and $2.6 billion in annual sales by 2020.
PlantLab, a group with a similar facility in the Netherlands city of Den Bosch albeit three floors underground, follow a similar path and suggests that, “No energy is wasted with light spectra that are not used or less used by the plant.
This means we can provide exactly the colours that the plant needs for photosynthesis.” Alas, LEDs aren’t yet as cheap as sunlight.
London has what’s been dubbed the world’s first supermarket rooftop garden. Food From The Sky is a project of Thornton’s Budgens supermarkets, growing organic produce on its roof and selling it directly to customers a mere eight metres below. Take that, Food Miles!
In the USA, Sky Vegetables’ vision is hydroponic greenhouses atop grocery stores complete with rainwater harvesting, green waste composting, aquaponics and renewable energy. In a similar vein, is Home Town Farms, who calculate their growing systems will use 70 per cent less land, 85 per cent less water, 80 per cent less fertiliser than conventional farming. Home Town Farms have attracted the attention of the City of San Diego, who this year received a grant of $50,000 to study the benefits of urban agriculture.
Closer to home, Melbourne City Rooftop Honey (aka Rooftop Bees), harvest honey for 25 cafes and restaurants from hives perched on the roofs on many of the very same establishments. Another enterprise, the Urban Honey Company tends more than 20 hives in city backyards.
Sydney City Council has a Community Gardens Policy guiding the direction of the 11 little urban farms within their precinct. One of which includes the street verge gardens of inner city suburb Chippendale, spearheaded by Sustainable House advocate Michael Mobbs. The council also aims to support other local food initiatives such as school kitchen gardens, city farms, and green roofs.
Fytogreen is a Victorian company who, although having focussed mostly on visually attractive green roofs and vertical gardens have the requisite technology and experience to transition into urban food production, if the right client happens along. As are the likes of Greenwall Company, Greenwall Australia, and Atlantis, with their Gro-Wall products.
For more horizontal plantings there are a whole swag of options.
The Little Vegie Patch Co. provides repurposed apple crates, ezyGrow’s polyethylene raised garden beds have a built in water dam in the planter’s base, allowing for balcony food gardens withoutleaky pots. Box My Garden makes Australian Cypress raised garden beds, with the Green Bean fabricating theirs from re-growth Red Gum. Others digging in much the same dirt include, The Instant Vegie Garden and Earthbox Australia.
There is so much to explore in this important junction between food production and urban construction that we do not have the column inches to do it justice. We reluctantly conclude then with a quote from professor and architect Alexis Rochas. Rochas designed SYNTHe, a 140 sqm rooftop food garden, made of sweeping curves of metal over a recycled plywood frame, atop of a downtown Los Angeles residential development.
“The architect becomes a gardener, the gardener a planner.”
