What is vertical farming?

Just as our homes have evolved to be stacked on top of one another to accommodate a growing population, so too have our farms. Vertical farming, or urban farming, uses controlled-environment agriculture (CEA) technology to regulate factors like temperature, humidity, and light to optimise plant growth. This increases productivity to help meet the growing demand for sustainably sourced food. 

Soil trays stacked on shelves with grow lights and hydroponic tower systems in greenhouses using natural sunlight are some of the common methods of vertical farming. But while these methods are considered modern farming innovations, the principles behind vertical farming date back millennia. 

The first known example of vertical farming is the Babylonian Hanging Gardens, built around 2,500 years ago. In the 1600s, French and Dutch farmers advanced vertical farming by growing warmer-climate fruits against heat-retaining stone walls, protecting the fruit from the cold nights. 

In the modern world, vertical farming has evolved as a critical solution to the looming food security crisis. By growing crops in vertically stacked layers, these farms are able to save a dramatic amount of space, increasing productivity per acre and guaranteeing a more sustainable and reliable food supply in urban areas.  

Growing environment:

• Traditional farming: open to the elements, traditional farming relies on open paddocks, seasonal changes, and natural weather patterns to provide the conditions needed to support agricultural production. Farmers depend on soil fertility and favourable weather conditions to grow crops, with production susceptible to climate and water variability, and pests, weed, and disease incursions.
• Vertical farming: vertical agriculture is based indoors, in controlled environments where temperature, humidity, and light are carefully regulated to ensure optimal plant growth. This eliminates the dependence on weather and provides a physical barrier to the entry of pests, weeds, and diseases. By allowing for precise nutrient and water delivery, vertical farming systems create a stable and predictable growing environment year-round.

Space utilisation:

• Traditional farming: requires large expanses of land to cultivate crops, making scalability a challenge in areas where land is scarce or expensive. Globally, the agriculture sector already accounts for around 50% of total land use. Expanding agricultural land use has traditionally been associated with deforestation and habitat loss, with 73% of global deforestation attributed to agriculture.
• Vertical farming: maximises space efficiency by growing crops in vertically stacked layers, significantly reducing land use. Vertical agriculture makes it possible to cultivate food in urban areas, such as converted carparks, abandoned warehouses, or as sustainability as a service startup, Farmwall, proves – even inside schools and office buildings. Vertical agriculture brings food production closer to consumers, while preserving natural landscapes.

Water usage:

• Traditional farming: consumes vast amounts of water, with much of it lost due to evaporation, runoff, and inefficient irrigation practices. Agriculture accounts for about 70% of global freshwater use, putting significant pressure on water resources, especially in drought-prone areas.
• Vertical farming: uses closed-loop hydroponic, aeroponic, and aquaponic systems, which recycle and recirculate water. These vertical farming systems reduce water consumption by up to 98% compared to traditional farming, making vertical agriculture a crucial solution for improving food security in regions affected by increasing global water scarcity caused by climate change.

Energy consumption:

• Traditional farming: relies on natural sunlight for plant growth, which limits crop cycles to seasonal changes. Broadacre farming requires fuel-intensive machinery and irrigation systems, contributing to greenhouse gas emissions.
• Vertical farming: uses artificial LED lighting and climate control systems to maintain ideal growing conditions in vertical farming systems. While this results in higher energy consumption, advancements in renewable energy sources and efficient LED technology are making vertical agriculture more sustainable, reducing its carbon footprint while maximising yield.

Crop yield:

• Traditional farming: crop yields are influenced by seasonal cycles, weather patterns, and soil conditions, leading to variability in production. Extreme weather events, pests, and diseases can also reduce output and cause crop losses.
• Vertical farming: delivers higher, and more reliable, crop yields by providing an optimised, highly controlled environment. Farmers utilising vertical farming systems can grow crops year-round, with faster growth cycles and multiple harvests per year, increasing overall productivity compared to traditional farming methods.

Cost:

• Traditional farming: setting aside the cost of the initial land investment, traditional farming comes with ongoing expenses like new land acquisition, machinery upgrades, inputs like fertilisers and herbicides, and seasonal labour. Market fluctuations, weather risks, and pest outbreaks can significantly impact profitability.
• Vertical farming: involves higher upfront costs due to the need for vertical farming infrastructure, technology, and energy, but offers lower long-term costs through automation, efficient resource use, optimised yields, and year-round production. As technology advances, vertical farming is becoming more cost-competitive with traditional agriculture.

Vertical farming is well-equipped to future-proof our global food supply. Traditional farming relies heavily on large expanses of land, which are becoming increasingly scarce due to urbanisation and climate change. Vertical farming, on the other hand, maximises land use efficiency so that farmers can reliably produce more food without requiring any additional land. Although space-saving is the primary advantage driving the growth and adoption of vertical farming in urban areas, it also offers numerous other benefits: 
 
- Year-round crop production: vertical farms can operate continuously throughout the year, regardless of external weather conditions, ensuring a consistent supply of fresh produce. 
 
- Water conservation: through techniques like hydroponics, aeroponics and aquaponics which circulate and recycle water, vertical farming systems use significantly less water than conventional farming.  
 
- Higher yield and faster growth: by optimising growing conditions with controlled environment agriculture (CEA), plants grow faster and produce higher yields when compared to conventional agriculture methods.  
 
- Reduced chemical output: the controlled environment of vertical farms minimises the presence of pests and diseases, reducing or altogether eliminating the need for chemical pesticides and herbicides that can be harmful to human health and the environment.  
 
- Local production: vertical farms are ideal for urban centres, reducing transport costs and the carbon footprint associated with long-distance food distribution. Local production also means food spends less time in transit and storage, which extends its shelf life and reduces the amount of food that spoils before it can be consumed. 

By stacking crops vertically instead of horizontally, vertical farming aims to save space without foregoing productivity. Vertical farming is mostly undertaken indoors as it doesn’t rely on soil, as demonstrated by Australian agritech startup InvertiGro which partnered with Woolworths to deliver Australia’s first in-store vertical farms.

Vertical farming systems use hydroponics, aeroponics or aquaponics to grow plants indoors. Hydroponic systems are the most common, and use a water solution to deliver essential nutrients directly to the root system, which grows inside a medium such as rockwool, expanded clay or hemp fibres. Aeroponics is a variation of hydroponics that involves spraying the roots with air or mist, while aquaponics reuses water that fish have been swimming in to feed the plants.

But what exactly do vertical farms look like? Demand for vertical farming systems is growing, and so too is the range of vertical farm shapes and sizes, from two-level systems in patio gardens to tall, automated systems in warehouses or greenhouses with multiple tiers.

Tower systems  

Tower systems use stacked columns to grow plants vertically, maximising space and ensuring optimal plant growth. They offer high yields per square foot, but require careful management to be economically viable. 

Rack system 

Rack systems grow crops on vertically stacked shelves or racks and often rely on artificial lighting and climate control systems for the plants to grow. 26 Seasons is a vertical farming company using a rack system to grow strawberries year-round. 

A-Frame systems   

A-frame systems use triangular frameworks to support vertical crop growth. Watering and nutrient management systems are integrated into the design and the space saving structure is well suited to urban areas and commercial settings.  

Wall-mounted systems   

Wall-mounted systems, or living walls, grow plants on vertical surfaces, making efficient use of space. They are ideal for urban settings and architectural integration and great for herbs, fruits and leafy greens.  

Hybrid systems  

Hybrid systems combine various vertical farming techniques to optimise space and diversify crops. However, these systems can sometimes face challenges in their complexity and costly management. Vertical farming companies like InvertiGro offer innovative hybrid systems that can be tailored for different purposes. 

As demand for urban farming grows, so too does the innovation and research to bring new technologies to market. A new modular channel system has been developed by Gaia Project Australia (GPA), which optimises space and power resource requirements to double plant yield when compared to other controlled-environment agriculture (CEA) methods.  

High Energy Consumption

Vertical farming systems rely on artificial lighting and 24-hour climate control technologies to maintain optimal growing conditions. While this ensures year-round crop production, it leads to high energy costs, making energy efficiency a key challenge. However, ongoing advancements in LED lighting, solar power, and other renewable energy solutions are helping to reduce electricity consumption and improve the sustainability of vertical agriculture.

Initial Capital Investment

The infrastructure needed for vertical farming systems, including hydroponic or aeroponic setups, climate-controlled environments, and automation technology, requires significant upfront investment. This can be a barrier to entry for new businesses. However, as technology advances and economies of scale improve, setup costs are gradually decreasing, making vertical farming a more viable option for long-term agricultural solutions.

Technical Expertise

Unlike traditional farming, which often relies on intergenerational knowledge of soil-based agriculture, vertical farming requires specialised technical expertise in areas such as controlled-environment agriculture, hydroponics, aeroponics, lighting systems, and automation. Vertical farm operators must understand how to balance nutrients, monitor plant health, and optimise growing conditions. As the industry grows, educational programs and training initiatives are helping to bridge this knowledge gap.

Adoption

The widespread adoption of vertical farming depends on its economic viability, accessibility, and scalability. High operational costs and the need for specialised technology can limit widespread implementation, but continued advancements in agtech and market support for local, chemical-free produce is helping toward making vertical farming a mainstream agricultural practice.

1. How is vertical farming sustainable?

Vertical farming reduces land use, minimises water consumption, and significantly reduces (if not eliminates) the need for chemical herbicides and pesticides. By leveraging controlled-environment agriculture (CEA), vertical farming systems enable efficient, high-yielding, year-round production.

Additionally, by localising food production, vertical farming helps reduce food waste and transportation emissions, making it a more sustainable alternative to conventional farming methods.

2. Are vertical farms profitable?

While initial setup costs are high, vertical farms generate strong profits through increased crop yields, year-round production, and the opportunity for premium pricing for locally-grown produce. Advances in automation and renewable energy are further improving economic viability.

Many vertical farms focus on high-value crops such as microgreens, herbs, and specialty lettuces, which command higher prices and ensure faster returns on investment.

3. Does vertical farming use less water?

Yes, vertical farming uses less than traditional agriculture due to its closed-loop hydroponic, aeroponic, or aquaponic systems, which recycle water. These methods eliminate runoff and evaporative losses, ensuring water is used efficiently and making vertical agriculture a crucial food solution for water-scarce regions.

4.  How much water does vertical farming save?

On average, vertical farming systems save up to 98% of the water used in traditional farming, depending on the system used and the crop grown. By eliminating runoff and evaporation, vertical farms maximise water conservation and contribute to more sustainable agricultural practices.

5.  What types of crops are grown in vertical farms?

Vertical farms commonly grow leafy greens, herbs, microgreens, and fruits like strawberries and tomatoes. Larger systems have successfully grown root vegetables, mushrooms, and even staple crops like wheat and rice, pushing the boundaries of what is possible in vertical agriculture.