Jason Wargent sees crop farming going vertical and joining the urban landscape. A flood of innovation is about to be unleashed

By Jason Wargent*

The past 50 years have seen huge change in agriculture and food production. Rapid increases in the use of farmable land and intensification of the use of agricultural inputs have both contributed to the significant yield improvements achieved for staple crops since the 1960s. Now we are in a new phase where the magnitude and diversification of agricultural innovation must be maximised to meet the growing challenges of the 21st century. Not only have we reached the peak of ‘simple’ agricultural intensification, but we also face significant climatic uncertainty, combined with a rapidly growing global middle class.

Taken together, the demands of modern and future agriculture are arguably very different to those at the start of the Green Revolution. An expanding middle class has obvious implications for demands on food quality and safety; in New Zealand, numerous horticultural players have developed strong market positions by supplying premium products at a premium price, e.g. novel kiwifruit varieties and wine possessing characteristic properties. The New Zealand farming experience highlights that there is ample opportunity to produce high-value food that tells a story about food quality, sustainability, geography, tradition or nutrition.

As land availability decreases in many parts of the world, and land costs increase, pressure for the pace of agricultural evolution to accelerate is mounting. That said, new paradigms for premium agricultural production are emerging.

Despite the fact that indoor farming has been part of the agricultural landscape for nearly 200 years, we arguably sit at the front end of a next great ag-revolution, where food is grown within a highly diverse, ultra-technological, indoor ecosystem of cropping environments. Indoor farming now has wide interpretations of meaning; the most historical incarnation is that of glasshouse production, used for hothouse tomato cultivation. Protected cultivation can also be equally applied to the use of tunnel or ‘hoop’ houses, usually clad in plastic materials or netting.

Both environments have seen huge innovation growth in the last 30 years, from the introduction of sodium-based artificial-lighting sources into glasshouses to increase crop productivity to the development of ‘smart’ polymer-incorporated claddings for tunnel houses, which can regulate the lighting or temperature environment for crops within. However, both types of crop system still rely on ambient local climatic conditions to greater and lesser extents, e.g. sunlight (therefore day length) and temperature.

The quest to optimise every aspect of a crop’s production cycle led innovators in the 1980s to conceive the first prototype ‘plant factories’, where crops were grown completely indoors, using artificial lighting and environmental-control systems. Some of this innovation was driven by the space race, and the desire of agencies such as NASA to develop food production systems which were fully closed loops, in which food crops could be grown from seed to harvest using artificial light and circulating nutrient processes, such as those exploited in hydroponic systems. Those early enclosed systems have subsequently inspired a generation of entrepreneurs and technologists in the present, where a range of indoor farming categories are flourishing.

One of the most talked-about categories is ‘vertical farming’, the practice of incorporating vertically stacked layers or shelves of crops, often to maximise space-use efficiency in limited-footprint buildings, e.g. converted or purpose-built warehouses in urban areas. Vertical crops are farmed in their entirety under isolated, controlled conditions, thus creating an exciting vacuum of opportunity for agri-tech. Vertical farming has begun to capture imaginations, with visions of former industrial spaces glowing with floor-to-ceiling LED lighting. There are now likely as many physical manifestations of vertical farming as there are opportunities or motivations associated with adoption of the practice.

Controlling the environment

As discussed earlier, full control over a crop is a clear advantage of fully-indoor production: it means complete mitigation of climatic influence, and therefore the potential to extend or manipulate cropping seasons. Climatic isolation also means buffering food supply (and arguably food quality) from turbulent, one-off events, such as exceptionally dry or wet weather periods, or from pest and disease pressures. Equally, there is the opportunity for control and enhancement of food quality and nutrition.

Plants are composed of highly complex, responsive signalling networks, capable of acclimating to an environment on the basis of different cues or stimuli. As many as 200,000 secondary metabolite compounds have been identified in plants, many of which are associated with implications for produce taste or nutritional qualities. As our understanding of the associated plant biology grows alongside advances in agricultural technology, those stimuli required to nudge plants into a particular taste or nutritional profile can be deduced, and then deployed in a controlled environment.

An oft-mentioned advantage of vertical farming is the strong potential for localising produce-to-purchaser dynamics. In urban environments, shipping times from vertical farm to customer have been quoted in minutes, as opposed to hours or days. The potential to fully integrate food production into what is a typical consumer lifestyle — an urban one — is a tantalising proposition for many food retailers and marketers. The reality of nutritious herbs being grown one block away from a major city food market could be a food marketer’s dream. That said, there are still a very limited number of published life-cycle analysis studies focused on vertical farming. Understanding the cradle-to-grave impacts of vertical farming from a sustainability perspective will allow for greater consumer understanding, and for tech advances to underpin exploitation of the related opportunities, e.g. energy efficiencies, nutrient re-use, co-location with larger-scale customers, packaging and storage. The question as to how a consumer comprehends the very nature of an indoor farm, set against the ‘locally grown’ perspective, will be an interesting value proposition to unravel over time. Does a local indoor farm carry the same cachet as an outdoor, sunshine-bathed farm?

As well as the attraction of isolating seasonal downsides or exploiting urban co-location, arguably one of the most exciting and valuable opportunities for vertical farming is the pure potential to foster agri-innovation of all kinds. Certainly, vertical farming would not exist now without the already-substantial innovation leaps that have taken place to date, for which there can be broader applications beyond full-indoor farming itself. Growing crop plants to full yield in an isolated environment requires an understanding of the very essence of agriculture: nutrients, water and light must all be understood and calibrated to a crop’s needs, and in a cost-effective manner. An obvious reality with full-indoor farming is that there is a capital expenditure that would dwarf many agriculture operations on a per-unit area basis. So the challenges are twofold: ensure cost-efficiency following the associated capex, and employ a substantial amount of cutting-edge, ‘grow-how’ to produce products that meet a premium price point.

Light could be the hottest topic in indoor farming: plants require light for autotrophic nutrition, and fully-indoor spaces lack it. The rise of LED lighting for crop growth has been exponential in the last five years, following not just the expanding interest in light for unlit indoor spaces but also as a replacement for more historical, heavy-duty supplementary lighting sources. LEDs offer the ability to control the light environment (or spectrum) to a far greater extent than has previously been possible.

One exciting challenge with LEDs revolves around the aim to blueprint the lighting requirements for different crops. Getting the light right for increased crop productivity or quality indoors requires innovation and experimentation — for instance, an appropriate mix and intensity of, say, red and blue light will be different for tomatoes versus capsicums. Similarly, ensuring that higher-value herbs that are grown indoors maintain aromatic or taste compositions that meet (or exceed) consumer expectations will require careful tuning of the light environment.

Urban co-location

The win-win for agriculture in general is that the pressure to innovate for fully-indoor farming will very likely lead to new knowledge or IP, which could be exploited in the future for all manner of farming. From the development of soilless plant production techniques to advances in energy efficiency and automation, not only must indoor farming deliver food that meets a premium price point, but also practitioners must maximise crop yields per unit area of production space — aims that sit at the very heart of agriculture challenges and opportunities this century. Given the current economics of establishing and maintaining a fully-indoor space, this maximisation of quality and yield is arguably vital for indoor farming to grow.

The US has been one of the most active parts of the world (as well as Asia) in nurturing fully-indoor farming projects. At present, however, the scale of full-indoor (vertical) farming operations is still a very small proportion of all farming space by volume. The types of crops which currently sit within a feasibility range for vertical farming also have certain limits at present. For example, shorter-rotation, higher‑value products such as herbs or baby greens are particularly amenable to vertical farming, whereas row/field crops such as corn or soy are largely untouched to date, although some micro-pasture full-indoor container systems have been developed for grasses. However, there have been few limits to date regarding the innovation endeavours of indoor farming entrepreneurs: for example, the farming of vaccines for the pharmaceutical industry. We are likely sitting at the narrow end of the funnel right now, with greater innovation leaps yet to come.

Indoor farming cannot (and arguably does not aim to) replace field-based farming. Significant scale will take a number of years to achieve, and there is a strong case for indoor farming to differentiate in terms of the categories of crops produced, the price-points and the geographical locations. While such a complementation-style model is the likely norm right now, it is hard to predict where indoor farming will reach to in the future given the opportunities and the entrepreneurial nature of the sector at present. The potential for hybrid-exchanges of agri-tech in and out of indoor farming to drive advances in other farming forms is strong.

In addition to production and innovation, one other vital outcome from the advent of indoor farming can be education. With urban co-location, and the intersection of multi-disciplines (science, engineering and marketing, to name a few), one weighty additional responsibility for indoor farmers is the translation and communication of the realities and opportunities of farming to a younger generation of future innovators. Using tools such as container/urban food gardens in schools, site visits and educational partnerships, further integration of farming into large urban areas is a necessary path for our farming needs and traditions to build and evolve over the next 50 years.


Jason Wargent is an associate professor at the Institute of Agriculture and Environment, Massey University. This article is an essay in Massey University's 2017 New Zealand Land & Food Annual - No free lunch. It is reposted here with permission. The New Zealand Land & Food Annual 2017, Edited by Claire Massey, published by Massey University Press, RRP: $39.99, available in bookshops nationwide.

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