Plants that grow in (green-)houses, containers or storage units, without any sunlight? This has been possible for some years now – is that what the future of agriculture looks like? Some are convinced so, others prefer their plants to be in the soil under the sky. We take a look at the latest developments and the current status in Indoor Farming and explain the basics.
This article is the first in our series revolving around modern agriculture, vertical farming and automatization in food production.
Indoor and Vertical farming
Indoor Farming seems to be rather self-explaining. Nevertheless, it shows up in many facets – what they have in common is, that plants grow in closed rooms. This can be whilst using natural sunlight, like in greenhouses. However, this is also possible in containers or warehouses with artificial light. The latter is also usually associated with vertical farming. Here, the plants are also grown at height - for example in racking systems, which allows more cultivation area on the same number of square meters.
In connection with these two terms, Controlled-Environment Agriculture (CEA) is also frequently mentioned - this term describes a technologized approach to agriculture in which the external influences acting on the plants are precisely controlled. This is also done in closed systems such as greenhouses, as only here is the plant shielded from the environment.
But Indoor Farming doesn't have to mean large-scale cultivation - systems for the home kitchen or office are also popular ways to harvest fresh herbs or salads. Since March 2021, an Edeka supermarket in Munich has also been growing herbs and salads directly in the store - thus avoiding long transportation routes. Customers can harvest their own food in the store through Indoor Farming.
Why the fuss?
The idea of the plant in the closed system is not a new one - already the Romans knew that plants behind glass panes can withstand lower temperatures than in the open air. Greenhouses have always been a valued means to avert environmental influences such as heavy rain and hail, storms or frost from plants, thus saving the harvest. Looking at the closed systems in vertical farms, there are further advantages: here, up to 90% less water is needed than in conventional agriculture. Pesticides and plant protection products are also hardly needed since insects and pathogens do not occur in such systems.
Indoor Farming concepts are also popular for research purposes: Variables can be isolated and adjusted comparatively easily to research how optimal growth is achieved and which conditions lead to higher yields. For example, it is possible to find out how growth and harvest times can be extended and how taste and appearance can develop optimally.
Automation can also achieve independence from other external factors, such as the availability of harvest workers. Robotic technologies that irradiate plants with UV-light or harvest fruit, for example, can make farmers less dependent on external factors such as the coronavirus or political tensions and wars.
A sustainable solution?
Less water and pesticides mean more sustainable production? Not always, as a 2017 study by ETH Zurich, commissioned by WWF, shows. Plant-based foods are usually ecologically more favorable than animal-based foods. The exact balance however depends primarily on the type of production and means of transport. Transport by air and fossil-fuel heated greenhouses have a particularly negative impact. The same applies to the regional cultivation of fruit and vegetables, which have to be grown or harvested using energy-intensive machinery. If these steps are done by hand in other countries and the local machine runs on fossil fuels, the import is sometimes worthwhile.
A solution to this problem is offered by greenhouses that use renewable energy - some even make use of waste heat from industry, which is also a sustainable solution. If such are used, consumers can rely on locally produced fruits and vegetables in the greenhouse with a clear conscience.
Lighting, which is often used in indoor farming, can also worsen the sustainability balance if renewable energies are not applied. Solutions such as transparent solar panels, which convert the sunrays that the plants do not need into light, are already being discussed here. Because not only the ecological balance is often worsened by artificial light - also the costs for farmers are enormously increased by it. For this reason, new solutions are constantly being researched, particularly in the area of lighting, in order to make greenhouse cultivation more sustainable both ecologically and economically.
Nature stays outside?
In order to keep pathogens and pests away from plants and the system, Indoor Farming systems usually use technical solutions - for example, cameras and image recognition software. This plays a particularly important role here, because once germs have invaded, the entire farm is in danger. Spreading here could lead to major crop failures - due to the confinement, this happens quickly if not reacted to in time.
In vertical systems, hydroponics or aeroponics are often used. Simplified, this means that the plants no longer grow in soil, but in nutrient solution or in the air under pollination with such.
Thus, the best and most important of nature is imitated without pests being able to penetrate the system. Sometimes this triggers skepticism among consumers, because such solutions often appear opaque and complicated from the outside. Even advocates of organic farming have not yet been able to use vertical farming products - the certification of products as "organic" has so far been tied to cultivation in soil. This is a criterion that hydroponic and aeroponic farms do not meet.
The future of agriculture?
So why do we still see fields and fields when Indoor Farming has so many advantages? So far, Indoor Farming has only been profitable for a few types of plants - lettuce and herbs are particularly common. Nevertheless, they are not a rare instrument - especially the Netherlands is known for its numerous greenhouses - some of them cover more than 70 hectares. No wonder, since more than half of the country's land is used for agriculture and horticulture. Vertical Farming "is particularly worthwhile for high-quality plants that achieve a high price per weight and are grown as densely as possible," says Prof. Dr. Heike Mempel of Weihenstephan Triesdorf University of Applied Sciences on the university's website. Indoor and vertical farming can also be an opportunity for pharmaceutical, cosmetic and medicinal plants, where consistently high quality is of great importance.
The integration of Indoor Farming into existing structures offers numerous possibilities - for example, with the cultivation of plants directly in the store, in large cities or underground garages.
A study from 2015 in the international Journal of Environmental Research and Public Health, which compared Hydroponic and conventional agricultural methods, concludes that „hydroponic gardening of lettuce uses land and water more efficiently than conventional farming and could become a strategy for sustainably feeding the world’s growing population, if the high energy consumption can be overcome through improved efficiency and/or cost-effective renewables.” Thus, it may take a while to get there – but more sustainable and profitable solutions for Indoor Farming are coming!