There are a lot of strong opinions on whether vertical farming is viable and sustainable, but one thing everyone can agree on is the basic definition: vertical farming is growing within a volume of space instead of on a single horizontal plane. By that definition, vertical farming has actually been around for a long time. And regardless of where and when it has made an appearance, its goal has always been the same: maximizing production within a given growing space.

Historically, farmers growing within a small space have used tall, vining crops, which naturally use vertical space more efficiently than short, statured crops. These early vertical farmers include rice farmers terracing paddies in Southeast Asia, and the architects of ancient Babylon, who built one of the seven wonders of the ancient world, the Hanging Towers of Babylon. These are some of the earliest examples of farmers looking at vertical space and imagining ways to use it for growing.

Vertical Farming Today

Modern vertical farmers are looking at vacant warehouses, the sides of buildings and, in some extreme cases, skyscrapers, to produce crops in large volumes relative to the square footage of the growing area. Almost all of these farmers use hydroponic systems to minimize the weight load and, therefore, the amount of infrastructure needed to support the equipment.

These farms are already incredibly capital-intensive and using soil or heavy, water-logged media would increase the amount of expensive steel and structure necessary to support the growing equipment. Hydroponic production using nutrient film or vertical plane techniques helps reduce these start-up costs for vertical farmers. Some farms also use aeroponics or deep water culture, although the costs of the support structure for raft production tend to be higher.

Vertical Farm Tech

There are two main camps in the evolving vertical farming community: stratified, or stacked, producers and vertical plane producers.

Stacked Production

Early vertical farmers took horizontal production techniques and stacked them up using pallet racks or other support systems. These stacked, horizontal systems were an obvious first step towards vertical farming, as most producers were already familiar with conventional, single-plane equipment. As a result, adapting conventional equipment in a new, stacked, layered configuration felt very natural.

This adjustment, while convenient, has caused many farms some issues. Most have consistently struggled with air circulation, heat removal, humidity and disease issues, and CO2 depletion in the plant canopy. They often also experience increased labor costs associated with tending and harvesting plants from a scissor lift. These issues have arisen from a failure to redesign production equipment for the unique variables that come with indoor, high-density growing.

Stacked producers have had to invest increasingly large amounts of money in automation, sensors and other systems in an effort to improve the performance of equipment that is often not designed for vertical farming applications. Despite this, some of these growers are gaining traction and finding success in their markets. The question that remains, however, is will they be successful as the market becomes more competitive?

Vertical Plane Production

Born from the frustration of dealing with the plant health issues and labor costs associated with stacked production, a few producers began to use a new orientation called vertical plane production. Vertical plane production involves growing crops sideways out of towers or panels, back-to-back, with aisles in between sections.

These aisles give producers easy access to crops from the ground and allow lights to be hung vertically between the two growing faces. This configuration achieves the same level of production as stacked producers, while lowering both capital and operating expenses.

In some ways, this style of production is similar to conventional greenhouse tomato production that uses inter-lighting, where crops are lit from the side. In this orientation, intense light is used to modify the orientation of the crop. Vertical plane production allows producers to operate from the ground, simplifying logistics and reducing labor costs significantly.

This production technique is rapidly gaining traction in confined growing environments like greenhouses, warehouses and even shipping containers, on both small and large scales.

The Future of Vertical Farming

Both techniques are being practiced in a growing number of vertical farms. Stacked farms have been around for longer, and as a result are typically better capitalized and more accepted in traditional vertical farming circles. However, vertical plane production is catching up quickly.

This is especially true of large numbers of smaller farming start-ups, which need to be more flexible. In fact, the most growth in the vertical farming industry is happening on a relatively small scale, in operations with less than 2,000 sq. ft. of production.

One thing is for sure: vertical farming is quickly becoming the most talked about and explored growing technique by new and existing farmers alike, regardless of scale. For smaller-scale growers (2,000 sq. ft. or less), emerging technologies and the increase in accessible educational resources are helping to lower start-up costs significantly.

While most people imagine that vertical farms will closely resemble the mega-farms of the past, it is more likely that in the future, these farms will be smaller, more widely distributed and more connected.

Equipped with the right know-how and tools, today’s vertical farmers have a lot going for them. New developments in modern farming practices, including innovations in LED lighting and environmental controls, have reduced the cost of production and increased the quality of produce on the market.

Culturally, local markets are also primed for what the modern vertical farmer has to offer. By leveraging their ability to grow in warehouses, on the sides of buildings and in other environmentally constrained areas, vertical farmers can bring a fresher crop to market and build a happy customer base.

However, truly accessible vertical growing still faces some constraints. Access to capital is a huge problem for large growers. Because of the capital-intensive nature of starting a vertical farm, large producers often have to raise many millions of dollars to get started.

The solution is to focus on small farmers and teach people how to farm vertically on a much smaller scale. The small-scale, distribution approach to vertical farming is finding significant traction and is rapidly eclipsing the traditional “bigger is better” mentality regarding vertical farms.

Education is the second major hurdle vertical farmers face. This is a new industry, and staffing vertical farms with knowledgeable, capable growers is a constant challenge. This is being overcome with the increasing availability of affordable, online courses and teaching platforms built specifically for modern farmers.

These services are teaching more people than ever before not only how to grow their plants better, but also how to run a business, raise money and manage personnel. Soon, master growers will no longer have a monopoly on growing knowledge. Democratizing the knowledge of how to grow is an important step towards a network of distributed food producers.

With emerging, software-based growing technologies, artificial intelligence, sensor technologies and the rising popularity of urban agriculture, as well as the general consumer trend away from conventional products towards local products, the future of vertical farming is bright. I believe vertical farming will be a powerful force for moving production closer to consumers, eliminating food deserts and reducing the environmental footprint of the crops we consume.