Context

• Addressing the rising global food and nutritional demand with a growing  global population, diminishing farmlands, declining soil fertility and  increasing urbanisation has prompted the adoption of advanced farming methods that are crucial for sustainable and efficient food production systems.  
• In India, 53% are expected to live in cities by 2050. Limited agricultural land for conventional farming necessitates the exploration of innovative food production technologies like Urban Farming (UF) including vertical and hydroponic farming, which can ease pressure on agricultural lands for a healthier and more sustainable future. 

Understanding Vertical Farming and Hydroponics 

• Vertical farming (VF) revolutionizes traditional agriculture by employing soilless cultivation in a multi-level, protected indoor environment, departing from conventional soil-based farming and horizontal crop growth on a single level. 
• Prof. Despommier is acknowledged as the founding father of ‘Vertical Farming,’ who created high-tech vertical farms as an alternative solution to address nutritional needs, particularly in megacities. 
• Vertical farming has the potential to enhance food production, maintain quality and contribute to sustainable urban farming. 
• It is an indoor urban technique involving large-scale food production within multistorey buildings. 
• Vertical farming adopts a unique approach to maximise space and efficiency by cultivating plants in vertically stacked layers or inclined surfaces, often within controlled environments like greenhouses or warehouses. 
• This method proves particularly advantageous in densely populated urban areas where space is limited, allowing for optimal use of available space. 

Nutrient-providing methods

• Various shapes and sizes of vertical farms worldwide employ one of three nutrient-providing methods: Hydroponics, Aeroponics, or Aquaponics.

Hydroponics: 

• This prevalent technique in vertical farming involves growing plants on soil-free substances continuously irrigated with nutrients. 
• Plant roots are submerged in a nutrient solution, and the system uses 60–70% less water than traditional agriculture, making it widely utilised in numerous vertical farms worldwide. 

Aeroponics: 

• Developed by NASA in the 1990s for space plant growth, aeroponics cultivates plants in a soil-free mist environment with roots hanging down in a closed-air container. 
• This method uses 90% less water than hydroponics, making it a highly efficient system of food production. 
• Plants grown aeroponically absorb more nutrients, resulting in healthier and more nutritious produce. 

Aquaponics: 

• Going beyond hydroponics, aquaponics integrates fish production into plant cultivation. The system utilises fish-produced nutrient rich waste as a feed resource for plants, and plants, in turn, purify and recycle wastewater for fishponds. 
• While this system offers ecological benefits, its complexity and higher cost make it less common in vertical farming. 

Advantages of Hydroponics

• Hydroponic farming presents an intriguing alternative to traditional soil-based agriculture by nurturing plants in nutrient-rich water solutions instead of soil, fostering quicker and more efficient growth. 
• This soil-less approach proves versatile, cultivating a diverse range of crops, from vibrant leafy greens to fruitful plants. 

Advantages: 

• Hydroponics in conjunction with vertical farming utilises 99% less land compared to traditional farming due to the concentrated root system.
• Hydroponics requires less water compared to conventional farming practices. 
• Enables the creation of a controlled microclimate, allowing year-round indoor cultivation of regional or seasonal crops. 
• Protects crops from soil-borne pests and diseases, and adverse weather conditions, thereby reducing the need for pesticides and fertilisers. 
• Vertical farming enhances plant productivity per unit area compared to horizontal hydroponic methods. 

Disadvantages 

• High upfront infrastructure costs pose a significant hurdle to widespread adoption. 
• Shortage of expertise and the need for a controlled growing system necessitate a highly educated workforce, leading to elevated labour costs. 
• It is energy-intensive and requires artificial lighting, temperature, and humidity requirements, which increases the cost of production. 
• The absence of natural pollinators in controlled conditions can result in poor fruit sets and the production of small, misshapen fruits. 
• The range of crops cultivated commercially is usually confined to leafy vegetables and microgreens. 
• Require continuous attention and care, with components like pumps and nutrient delivery systems needing regular maintenance. 

Way Forward 

• Vertical farming, though expensive, is more affordable by utilising cheap and available shipping containers and abandoned warehouses. 
• Collaborative research is important to bring together current technology practices for increased sustainability. 
• Hydroponics and vertical farming offer efficient and sustainable solutions to urban agriculture challenges. 
• Hydroponics maximises resource use, enables yearround crop production, and increases yields, potentially revolutionising food cultivation, especially leafy vegetables. 
• The integration of smart technologies and automation enhances agricultural productivity in vertical farming. 
• While hydroponics and vertical farming can be a good solution, they need more acceptance for widespread adoption. Research shows that supportive policies and incentives, like grants and tax benefits, can encourage investment and promote urban agriculture through agri-startups.