This article was written by Jorge Luis Alonso G., an information consultant specializing
in the potato crop.
Scientists at the Norwegian Institute of Bioeconomy Research have conducted a study to present an alternative hydroponic system for growing potatoes using raw wood fiber as a growth medium. The research team published a scientific paper in the journal Npj Science of Food recently.
This article is a summary of the study.
With a growing population and unpredictable markets, the future of our global food system is under immense pressure. It is currently failing to provide enough nutritious food in a sustainable way. Looking ahead to 2050, it’s predicted that our global population will swell to 9.7 billion, requiring 70% more food, a figure that doubles in the developing world.
Traditionally, the answer has been to convert more land to agriculture, even though this approach sometimes damages biodiverse habitats and doesn’t necessarily guarantee food security. Sustainability and balance must therefore be seen as equally important goals.
At the same time, an unprecedented wave of urbanization, particularly in sub-Saharan Africa and South Asia, is reshaping food systems. This shift is leading to increased demand for nutritious, processed products, the conversion of agricultural land to residential or industrial use, and the creation of more complex market dynamics.
As agricultural land becomes scarce, food production is either intensified on the remaining land or shifted to non-agricultural urban and peri-urban areas. Despite the challenges of land acquisition, these urban farms are critical to food security for many in low-income countries. There’s an urgent need for innovative cropping systems and technologies to produce food in areas where land is limited.
Potatoes, the world’s third most consumed food crop, offer a promising alternative. It yields more per unit of land in less time than any other major crop. Despite shrinking acreage, global production will reach 360 million tons by 2020.
Interestingly, unlike major cereals, potatoes are unaffected by international commodity exchanges, making them immune to speculative market activity. Potatoes also help diversify local food systems, typically dominated by cereals, making them more resilient to crises.
However, climate change poses a significant threat to potato production, particularly in southern Africa, India and the tropical highlands. In response, there is an urgent need to explore alternative systems to ensure global food security. These could include expanding potato production areas or using climatically unsuitable or degraded land.
In the face of these challenges, hydroponics, a soilless growing method that uses a nutrient solution, appears to be a promising alternative. This system reduces dependence on arable land and soil, reduces the incidence of disease, and provides resilience to extreme weather events. In addition, it uses precise fertigation, which significantly reduces irrigation requirements and fertilizer-related N-leaching losses.
While aeroponics has recently been used for potato seed production, hydroponics provides a less complicated root environment. It ensures optimal aeration, water and nutrient supply through the use of growing media or “substrates”.
This study proposes an alternative hydroponic potato system using wood fiber, a renewable and recyclable material. Wood fiber has a lower environmental impact than traditional substrates and has shown potential for potato growth. Such a system could serve as a valuable tool for policy makers seeking to improve food production in land-limited areas, or as a model for urban agriculture.
The study further tests the hypothesis that hydroponically grown potatoes differ in quality from conventionally grown potatoes, provides technical details for replication, and discusses potential challenges and opportunities.
In addition, hydroponic potato production using wood fiber substrates could help alleviate growing food insecurity, which is exacerbated by dwindling land resources and increasing urbanization. As agricultural land reaches its capacity and urbanization consumes fertile land, there is a need for alternative, efficient growing systems.
Hydroponic systems, which are less dependent on weather and more predictable in production, offer a promising solution. This is especially true when the wood fiber is used as a substrate due to its high porosity, airiness and lower carbon footprint. This system also offers the possibility of biofortification of crops, a process that could prove vital for vulnerable societies.
The proposed system, which is designed to be simple and scalable, involves filling plastic bags with wood fiber to serve as a growing medium. It’s important to note, however, that it requires careful irrigation management to maintain optimal moisture in the root zone.
Despite this caveat, the system has demonstrated the ability to produce significantly higher yields than traditional field cultivation due to improved root oxygenation and nutrient availability. In addition, the use of recyclable, renewable wood fiber as a substrate is consistent with the goals of sustainable intensification and environmental stewardship.
Adding to its appeal, the system’s cost-effectiveness due to minimal equipment and inexpensive raw materials increases its potential for widespread adoption. The system’s simplicity, environmental benefits, and adaptability make it a promising alternative for future global food security. This development also underscores the need for continued research and innovation in sustainable urban agriculture.
Compared to traditional field methods, the system delivers superior results, catapulting yields to new heights while maintaining the tuber’s dry matter content and nutritional value. Designed for ease of implementation and scalability, it stands strong in the face of resource scarcity, proving its ability to ramp up production with ease.
Of course, this innovation isn’t without its challenges. Precise placement of seed tubers becomes critical, and production cycles can be extended due to increased biomass production. There’s also the risk of tuber deformation due to increased moisture in the tuber zone. To address these challenges, they are developing two unique irrigation strategies. One aims to maximize yield and nutrient content; the other focuses on increasing dry matter content while reducing tuber defects.
Finally, the nature of hydroponic production shines through, demonstrating the system’s ability to fine-tune pH levels and the macro- and micronutrient composition of tubers. By using wood fiber, this system paves the way for biofortification and marks the beginning of a new era in sustainable agricultural production.
Source: Kusnierek, K., Heltoft, P., Møllerhagen, P. J., & Woznicki, T. (2023). Hydroponic potato production in wood fiber for food security. Npj Science of Food, 7(1), 1–9. https://doi.org/10.1038/s41538-023-00200-7
Cover image: Credit the authors and publisher of the scientific paper