Vertical farming, an innovative approach to agriculture, is gaining traction worldwide, with its global market value expected to reach an impressive $23 billion by 2029. This soilless cultivation method typically takes place in vast greenhouses or warehouses, where plants are stacked high on rows of shelves, and parameters such as lighting, temperature, and humidity are controlled by computer systems. Despite its high-tech appearance, the premise of vertical farming is simple, plants are grown without soil, with their roots in a solution containing nutrients.
There are three main types of vertical farming: hydroponics, aeroponics, and aquaponics. In hydroponics, plant roots are held in a liquid nutrient solution, while in aeroponics, roots are exposed to the air, and a nutrient-rich mist or spray is applied to them. Aquaponics, on the other hand, utilizes nutrients from fish farm waste to replace some or all of the chemical fertilizers delivered to plants through hydroponics.
While vertical farming has the potential to produce a significant amount of food, there are four key myths that need to be dispelled. Firstly, some people may worry that vertical farming puts traditional field cultivation at risk, but this is far from the truth. Currently, vertical farming is only profitable for a limited range of small, fast-growing, and high-value plants such as lettuce and leafy greens. Although costs are expected to fall due to economies of scale and standardization of processes, allowing for a wider range of crops to be grown, there is an ethical issue to consider, just because something can be grown in this way doesn't mean it should be.
Secondly, while vertical farming is a nice idea, it's not currently a reality that it will feed everyone. Most vertically grown crops are sold at a premium due to the high capital expenditure required for infrastructure and the energy-intensive nature of the operation. Some researchers suggest that city-based vertical farms can help address nutritional food deserts, but for this to be scaled up, costs must come down.
Thirdly, the argument that vertical farming isn't sustainable typically derives from the fact that it requires electricity to run. However, a decarbonized grid running on 100% renewables makes this point moot, and many commercial vertical farms already source their electricity from renewable energy providers. In some ways, vertical farming can be more sustainable than field production, as it is a closed-loop recirculating system that reuses water and fertilizer, and there is no effluent run off into the environment.
Lastly, the notion that vertical farming isn't natural is subjective. Vertical farming essentially uses technology to mimic processes and environments that exist in nature, without manipulating or defying natural processes. LED lights mimic sunlight and can even be programmed to improve light ratios and help plants grow faster with higher levels of nutrition, while the fertilizers used are composed of the same elements as those used in the field.
In conclusion, vertical farming is a complementary method of producing food closer to end users, with more control and a higher land-use efficiency. It can build systemic resilience within our food system, as vertical farm yields won't be vulnerable to extreme weather events due to climate change, and it can enhance local food security that might otherwise be at risk from increased political unrest abroad. While vertical farming is currently limited in the crops it can produce economically, by incorporating these technologies into the transition to more regenerative and nature-based farming practices, it could have wider environmental benefits.
