Time to rethink hydroponics?
In a time when pandemic, climate change and political insecurity could disrupt our food supply, is it time to rethink permaculture’s reluctance when it comes to hydroponic farming?
DOES THE PANDEMIC suggest that it is time to rethink what we believe about how food is produced?
We don’t have to look far to find a distain for unconventional food production systems in permaculture. Mention hydroponics, and we are flooded with comments about synthetic inputs, the lack of soil-borne minerals, the energy costs of operating the system and the superiority of soil-grown food.
I recall permaculture co-founder, Bill Mollison, criticising hydroponic growing over 25 years ago. Then, he might have been right. But, when we look at how our food is produced and, just as importantly, how it is distributed, is it time to revise our thinking? The world, our cities, have changed since Bill made his comment. Back then the issue of urban food security was low-profile and was not factored into his comment that I recall.
Now, with food security garnering a higher profile thanks to the challenges brought by the coronavirus, perhaps it is time to take a fresh look at hydroponics. If we can grow food on rooftops and in car parks, especially in marketable quantities and especially if it is affordable to low-income people—and with the job losses the pandemic brought and with the nation heading intio recession that is now a larger number—can we not make the urban food supply more secure?
Food is a minefield of values, opinion, science and assumption. In raising hydroponics as a devils-advocate (*) question we are likely to encounter the familiar ‘natural’ versus ‘artificial’ argument.
A question of inputs
The difference in health outcomes is unclear. That was the conclusion of the Mayo Clinic when it compared organically grown food to conventional. The popular assumption is that organic is better, but how much better? The Mayo Clinic says that organics does offer some benefits over conventionally grown, however these are small to moderate increases in some nutrients.
Organics began its rise to popularity in the 1970s and is now a substantial industry. Touted as purer than food grown with synthetic agricultural inputs and as less damaging of soils, second thoughts about organics started to creep in when people realised there was more to organics than nutrition and farming inputs. Just like conventionally grown food, organics is controlled by large corporations, is reliant on botanical chemical inputs to control insects and plant disease rather than being chemical-free and, like conventional foods, is grown in monocultures. Home grown organic food and that grown in small market gardens might avoid corporate control and monocultures, however it does not account for the bulk of organic produce coming onto the market.
Hydroponics does away with the need for soil as a growing medium, substituting plant nutrients carried in water to the plants’ roots. Aeroponics does the same by distributing nutrients in water vapour.
When we compare organics and hydroponic growing, citing a greater proportion of nutrients in soil-grown food as evidence showing hydroponics is inferior rests on the assumption that those nutrients cannot be supplied in hydroponic systems. Whether they can is an argument that resurface from time to time and that is never convincingly settled.
Arguments against hydroponics often focus on synthetic inputs. It is true that most hydroponic farms use synthetic inputs, however the argument starts to fall apart because the conventional farms that produce most of what people eat also rely on synthetic inputs. Sure, organic farms are different, however when people use the inputs argument by itself they disregard the reality that organics consumes plenty of embodied energy in the inputs it uses, including fossil fuels, as does farming and hydroponics using synthetic inputs.
What about developing a hydroponic system that uses organic farming inputs? There has been work on that over the years. If adopted, would organic farming certification agencies recognise the produce as officially organic in the absence of soil? If not, then perhaps organics should be reclassified as ‘organic soil grown’ or the agencies method of classifying organic produce changed.
Hydroponics is a well-established commercial farming system already supplying vegetable nutrition to both city and rural people. It has been doing this for years and there is no consensus around it having any detrimental health impact compared to comparable soil-grown fresh foods.
Plenty of urban open space?
Hydroponics is well-suited to food production on paved surfaces and rooftops in densely-populated cities. Here, and in sufficient quantity, it could complement urban-fringe farms in underwriting the food security of the population.
People say we do not need hydroponic production in the cities because there is plenty of open space that could be farmed. Australia’s Gardens For Victory campaign during World War Two is sometimes cited as evidence that urban land could be repurposed for farming. As the saying goes, that was then. Then, most people lived in detached suburban houses with large backyards. Now we have a much larger population many of whom live in apartments (20.7% of NSW dwellings in 2016, a 78% increase between 1991 and 2016 to one occupied apartment for every five occupied houses in Australia; source: ABS) and similar housing without access to land. Newer subdivisions leave very little open space around houses, which are tight-packed. There is some truth in the argument, however it is now a much smaller truth than it was.
Reinstating a modernised Gardens For Victory program during a prolonged crisis would be a wise move for government. One of the reasons I spent years assisting people to set up community food gardens was so that in a crisis those community gardeners would form a corps of trainers who could go out to assist new gardeners to get started. Community garden production would need scaling-up in a crisis. A renewed Gardens For Victory program could set the legislative scene to take it to market gardening scale.
There is no mistaking the bias towards food and farming in permaculture, including in the cities. It is not misplaced, however it at times disregards the other valid uses of urban land. I recall a prominent permaculture figure at a conference who added up all of the open space in Melbourne and implied it could be turned to food production. Urban systems are not that simple. It is true is that there is plenty of open space that could be cultivated even in our big cities, however much of it is found in suburban backyards that are not gardened for food and where home owners have no intention of doing so. That remains the situation despite the upsurge in home gardening during the panemic. Open space has to fulfil a range of uses other than food production. Passive and active recreation — important to the mental and physical health of urban people — sports and nature reserves are just some of these.
Not all apparently-unused urban land is suited to food production. An example: when working in local government as community gardening and landcare coordinator, a group of people in the densely-populated inner core area wanted to start a community garden on an unused patch protected by a high wire fence. Fortunately, rather than cut an opening in the fence and start a guerrilla garden as another group had done (I persuaded the council property department not to toss them out as they were using a site that cost council funds to maintain, and because the gardeners knew it was a site destined for sale) they contacted the council about the site and learned the reason it was fenced because of the presence of dangerous contaminants in the soil. The site was scheduled for remediation as part of the developer contribution for construction of apartments adjoining the site.
Seen in its multiplicity of land uses, urban open space can be in limited supply especially in the higher-population inner-urban region and zones of higher-population-density around major rail links.When I worked with City of Sydney I learned that there was only 200ha of open space for all uses for a concentrated and growing population, around 80 percent of which lives in apartments (https://www.cityofsydney.nsw.gov.au/live/residents/apartment-living). That in itself can be an argument for hydroponic food production on paved surfaces to provide local, fresh foods and small scale, local economic development.
Reducing risk with hydroponics
The coronavirus crisis highlighted the risks around food production, but especially around the food distribution system. The National Farmers’ Federation spoke out in an attempt to quell panic buying when the partial shutdown of the economy and society was announced. There is no food shortage, the Federation said, only an artificial shortage bought on by panic buying. Later, RMIT ABC FactCheck verified the federal agriculture minister’s and others’ claim that Australia has a high degree of food security: “…the nation produces an abundance of food, exports far more than it needs, and has ample alternative sources of certain foods should they become scarce”, FactCheck reported.
That suggests there might be no need to boost food production in and close to our towns and cities irrespective of whether it is soil or hydroponically grown, organic or otherwise. What it leaves out is how access, health and economic reasons leave some people food insecure, and the vulnerability of food production and distribution to disruptions from outside Australia’s borders.
The link between income and access to nutritious food became prominent over 15 years ago, thanks to the work of advocacy organisations like Sydney Food Fainess Alliance. Inner Sydney’s Food Distribution Service, a grant-reliant NGO delivering food to low income people with disabilities, was another initiative addressing food insecurity at the time. It demonstrated how social enterprise using not-for-profit business structures to satisfy social goals could play a role in increasing urban food security for vulnerable populations. Social enterprise, such as food hubs and urban box schemes, however, went on to service largely middle class speciality markets demanding organic and, often, regionally-produced foods. Low-income food insecurity persisted. Would there be potential here for local food producers using hydroponic methods to produce fresh foods in the areas where they were most needed?
The risks of conflict
Imaging a conflict in the Indo-Pacific region is no longer something strategists do in idle moments. It is now all-too-likely thanks to the strategic competition between the US and China. Were it to escalate and shipping routes be disrupted, trade would be affected including the transportation of liquid fuels. How would that affect our food supply chain which, like the rest of the economy, is reliant on a continuous flow of oil? The threat to national security in our region, with its threat to fuel supplies, is now as great as it was during the Cold War.
The supermarkets’ just-in-time delivery system trucks food and other products from regional distribution centres to the supermarkets. Despite disruption, it proved robust enough to sustain the food supply during the coronavirus. Whether it would cope in a crisis which brought a shortage of transport fuels, even where fuel rationing prioritised food delivery, is doubtful. That’s according to a recent report by the Defence Director of Preparedness and Mobilisation. The report disclosed the likelihood of the nation’s supply of diesel going into shortage by the second week of a crisis that shut down the fuel supply line. The transportation of goods would be affected within the first month and food supplies would begin to run out around the same time. Fuel supplies would be exhausted by the second month.
Would the federal government’s purchase of a fuel stockpile and storing it in the US because of a lack of Australian storage capacity compensate for the shortage? That’s questionable. It depends on the security of shipping routes, the availability of tankers and how long the stockpile would last in supplying fuel to essential services. Clearly, this is a significant vulnerability for Australia.
Another potential risk to our food supply chain is cyber attack. This is an ongoing challenge. Recent cyber attacks on MyBudget, Bluescope Steel and Toll, the national transportation company, are just the latest of others that include cyberattacks on medical research centres and hospitals in different countries. Cyber disruption of communications and transportation has the potential to disrupt food distribution. It is likely the transport sector would be targeted in any regional conflict Australia was involved in. With cyberattacks targeting transport, communications and medical services among others at the same time fuel supplies are cut off, we would have the synchronous systems failure Thomas Homer-Dixon warns about in his book, The Upside of Down. Synchronous failure is the most difficult to deal with. We see that in the impact of the coronavirus.
As in supplementing the production of regional farms in feeding the cities and vulnerable low-income populations, is there not potential for a hydroponic farming industry in the cities of a scale sufficient to produce quantities of fresh food in a national security crisis?
What about other systems?
Are there better systems than conventional hydroponics in the pipeline? To answer that we should look to the US and Chinese space programs.
Space is a long way from the soil of our farms. Spaceflight crews, though, have to eat. Now, with both China and the US giving serious consideration to crewed spaceflights to and even establishing bases on the moon, and Elon Musk’s Space X’s planned Mars landing, the energy costs of flight crews taking all their food with them and of continual resupply from Earth is too great.
Both NASA and China are working on mini-farms that would allow onboard fresh food production. Plants have been experimentally grown on board the International Space Station to learn about their growth in zero-gravity environments. Now, a new iteration of the onboard farm is under development, one which is more or less a closed loop system.
This new food production technology is billed as ‘bioregenerative’ because it is said to be self-sustaining. The system produces food, oxygen, filtered water and processes grey and blackwater using either light brought in from outside or via LED lights. It is said to be capable of producing 50 percent of an astronaut’s food supply, 100 percent of their water needs and 100 percent of their oxygen.
The farmlet would make use of the nutrient-misting system known as aeroponics. It does not need the bulk and weight of a hydroponic growing medium (usually perlite) and pumped water, resulting in significant load reductions and fuel payoffs for launch vehicles. Plant disease is easier to manage in a closed environment. The farmlet consists of a greenhouse around two meters diameter and six metres in length which telescopes to a metre long for transportation. China is reported to be working on similar technology and to be more advanced.
Potentially supplementing this are experiments in synthetic, animal-free meat — lab meat — whose production is based on stem cells. Lab meat remains in the prototype stage, however there is already resistance to it among many involved in conventional as well as organic farming and food systems.
The space programs of various nations have yielded useful technologies. GPS navigation, weather reconnaissance, communication satellites for our phone calls and internet browsing, search and rescue satellites, landuse monitoring and so on. Would scaled-up iterations of the farmlets designed for long-distance space voyaging, orbital and lunar stations become another benefit of the space program, this one feeding people in high-population-density cities in a world dealing with possible agricultural shortfalls in a climate-change future?
The case
Let’s summarise the case against hydroponics. First, it is said to be deficient in a number of nutrients present in soil-grown food. If it is not an organic production model—it uses synthetic inputs. Energy is consumed in its opertion. Additional to these is sentiment, the sentiment that ‘natural’, meaning soil-grown and organic, is better.
What about the case for hydroponics? First, it has the potential to increase local food production in densely-populated cities. It makes use of paved surfaces and open space unsuited to soil-growing. It could be scaled-up to a commercial level of production and in doing so be affordable to lower-income people presently disadvantaged by the higher cost of organic and local foods. There are models of organic hydroponic growing.
We might prefer vegetables grown in the soil and meat grown on cows, however in a fresh water, climate and crisis-challenged future with possible food shortages, and with long and vulnerable food and fuel supply chains, we might not be able to be too choosy when it comes to hydroponics.
The challenge: adapting to new realities
What people do when presented with information that the world has changed substantially is rethink what they previously believed. Would doing this allow those with sufficiently open minds to rethink urban hydroponics as a partial bulwark against disruption to the food supply as well as establishing a new source of locally-grown foods and stimulating local economies?
We are talking about the resilience of the food supply system to prolonged disruption. Is the distain among some permaculture and regen agriculture practitioners a reason to forget production systems that do not make use of soil? I don’t think so. Another reason I don’t think so is because we are coming into a climate change scenario that might reduce farm productivity.
With the uncertainties we face in the near future highlighted by the disruption brought by the coronavirus, it makes no sense to discard a potential food production option because it does not meet the standards of those wedded to soil-based food production.
(*) Playing ‘devil’s advocate’ is to take an opposing viewpoint or raise an objection to a claim merely for the sake of argument. You do not actually have to believe what you are saying when you raise these questions or objections; you are simply arguing in order to clarify issues and generate debate. This is a skill that requires considerable practice but when executed well, offers new insights, challenges stagnant thinking, and increases the rigor of debate and level of understanding. http://www.readwritethink.org/files/resources/lesson-docs/HowtoPlay_Devils_Advocate.pdf
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