Vertical farming is an antiquated idea that received a facelift in recent years. While the ancient Babylonians were celebrated for their hanging gardens, today’s vertical farmers use technology to assist their efforts. Vertical farming aims to maximize the crop yield per square foot. I.e., getting the most amount of food to grow using the vertical space above the ground. To achieve these goals, vertical farmers employ several vertical farming systems designed to maximize the growth potential of their crops while controlling various aspects of the process. Below We investigate some of these different vertical farming systems.
Vertical farming is a diverse method of farming. There is no one “magic” system as vertical farming occurs in various locations and adapts to the farmer’s needs, capacity, and budget. Most vertical farming systems are automated and employ a hydroponics system. Aero- and aquaponics are also viable.
Vertical farming is a fantastic way to move towards sustainable living. The best part about a vertical farming system is that anyone can do it, as long as you have a wall. Although vertical farming fits your needs and capacity, some systems are better than others. Here’s everything you need to know about a vertical farming system.
Vertical Farming: How It’s Done, Why It’s Good, And What It’s For
Agriculture is one of the foundations of civilization. Without it, we would still be hunter-gatherers looking for our next meal. Since the onset of agriculture, communities grew and developed into the world we’ve inherited today. Over the millennia, farming techniques morphed and adapted to suit their environmental pressures and society’s needs, and farmers who could not adapt were replaced by those who could.
Our current iteration of farming requires maximum output with dwindling resources. Land (physical space), water, and nutrient-rich soil are becoming scarce, and farming practices need to develop. Many of us are also trying to move to a sustainable lifestyle, where we produce our food but don’t have access to a plot of land. Enter vertical farming.
How Does Vertical Farming Work?
Vertical farming is not limited to a specific tract of land. It is often conducted in a repurposed building, and it maximizes the amount of crop produced within a smaller space by not spreading horizontally but rather using the vertical space. A vertical farming system either stacks growing trays one above the other or allows you to grow plants on a vertically inclined surface (like a wall).
A critical element of vertical farming is it is a type of Controlled Environment Agriculture (CEA). A CEA is a fancy way of saying we manipulate all aspects of the environment to promote productivity in crop production.
Specifically, farmers manipulate factors to the needs of plants so they precisely receive what they need to flourish. Environmental factors like temperature, the amount of light, nutrients, etc. These systems are usually hydroponically enriched.
The incredible part is that this manipulation is often so precise that we can grow multiple species, with varying needs, in the same building when we control the water, temperature, light, and nutrients in these systems, which results in plants receiving their exact needs without wastage of water, nutrients, or space.
What Can You Grow With a Vertical Farming System?
Although some commercial farms grow an array of crops, for the most part, around 57% of vertical farming is limited to leafy green vegetables. These vegetables are easier to grow as they require less height (when stacking growing trays/tiers, height becomes a limiting factor).
The most commonly grown plants in a vertical farming system include:
- Collard greens
Aside from these greens, farmers also grow certain herbs, including:
The type of plant used in a vertical farming system usually has a smaller growth form and a quicker growth time. Additionally, plants that are usually vulnerable to herbivory by pests (slugs, snails, grasshoppers, etc.) benefit from vertical (indoor) farming.
Other crops grown in vertical farms include:
- Cannabis (depending on local legislation)
Consequently, you could even grow taller plant species and then use them as growth supports for other crops:
- Brussel sprouts
What Is The Best Vertical Farming System?
Although aeroponics is the best method for a vertical farming system, it is not the most popular method. “Regular” hydroponics is a widely used system for its ease and availability. Whether aero- or hydroponics, the important factor is that the system is automated. Most of the important variables are set on timers and sensors by automating the system, which means the system adapts to changes before they become issues.
The best location to establish a vertical farming system depends on your capacity, needs, and finances. Are you starting a vertical garden in your back garden? A greenhouse or old shed are ideal options to start your garden. If you begin to expand, a tunnel would be the next step.
If you’re trying to start a small-scale business, a vertical farming system in a shipping container is a cheaper option that still provides sufficient space for growth. An old warehouse will be a great next step if you want to expand.
The beauty of a vertical farming system is that it’s dynamic and adaptable enough to work almost anywhere, provided you can control the environmental factors (temperature, lighting, nutrition, watering, etc.).
One of the critical factors is whether the vertical farming system benefits the type of plant you decide to produce. If your “cash crop” grows well and you and your plant are happy (you’re not spending huge amounts of money on upkeep, and there are great yields with little loss), you’re in the right spot.
The Best Types Of Vertical Farming Systems
There are numerous types of vertical farming systems, but most are located in a building or shipping container. What makes a vertical farm “good” is if it meets your needs, saves on resources, and is cost-effective.
Some of the best options for establishing a vertical farming system include:
Shipping Container Growing Systems
As the name suggests, vertical shipping container farms are established in 40-foot shipping containers.
The great part about shipping container (or freight) farming is that it is possible to set up practically anywhere in the city, which means that the distance between where you grow the food and where you sell it is negligible.
Seedlings and adult plants grow in the same container in different sections so that you maintain the optimal growing conditions for each plant through the various growing phases. We control all the elements inside these containers. You apply the nutrients and water via one of the hydroponics application systems; control the lighting (mostly LED lights, with various red to blue ratio lights) and the temperature.
Seeds usually grow in trays within these systems, while mature plants grow vertically in panels; however, there are variations as some plants grow in tier layers. According to American Shipper, the containers manufactured by freight farms produce an estimated 1000 heads of lettuce every week.
These vertical farming systems are usually extensively automated, efficient, and modernized. The most significant drawback to these systems is the amount of electricity used. The following video provides some great insight for more information on this type of farming.
Automated Vertical Farming Systems
Most commercially orientated vertical farming systems are automated, and for a good reason. Automated farms look the same as other vertical farms; however, a computer monitors and controls all aspects of the farming.
That’s not to say that there is no human involvement. Even vertical farms require our input in programming the required parameters (how much light, nutrient levels, airflow, etc.) and planting, transferring, and harvesting the plants.
However, the computer system takes over once you’ve set the parameters and placed the plants. Most will monitor and automatically control:
- The nutrient levels within the water to make sure that the plants receive the correct dosage at the correct time intervals, reducing waste.
- The pH. Plants require a specific pH to flourish. An automated system adds chemicals to ensure that the pH is within the correct parameters.
- Temperature. Critical for any farming operation is the temperature. The farming software knows when to switch on air-conditioning units/fans to regulate the temperature.
- Lighting. Another critical aspect is the duration and intensity of light provided to plants. Automated systems work on timers that turn the lights on and off as needed.
- The growth rate of the plants. The computer monitors the growth rate of the plants on the farm and provides you, the farmer, with feedback so you can “tweak” the system as needed.
- Carbon Dioxide levels. Important for plant growth and production is CO2. An automated system will turn on a CO2 pump to increase the density available to plants inside the air.
These systems need to monitor and correct any discrepancies by adding or removing certain elements to bring the system back within the parameters. Automated systems are fantastic in how they control these modernized systems in ways that people will not always be able to. I.e., these systems run 24/7, with no coffee or toilet breaks, and accurately correct any issues that crop up.
The fantastic news is that many of these systems link up to your smartphone, allowing you to monitor the farm from wherever you are. The most significant downside to these systems is that your entire farming operation is compromised if there are any system errors or electricity issues.
Vertical Sustainable Farming
As we draw closer to the end of arable land, farming practices like vertical farming become increasingly important. The purpose behind any vertical farm should be to reduce the carbon footprint generated through traditional agriculture in every aspect.
Not only should vertical farming preserve arable land and horizontal space, but should also reduce the number of fossil fuels consumed through better farming practices and location. I.e., vertical farms should be located closer to communities/end users and therefore reduce logistical costs and pollution.
Vertical farming practices also need to reflect a sustainable mindset, recycling waste, limiting water usage, and using alternative energy to power as much of the farming system as possible. Establishing a rainwater collection system supplies you with good quality, sustainable water, while solar power charges batteries to power the lights inside the farm.
Another issue with reducing waste and improving sustainability is how you package the harvested crops. In an article by Forbes, one farmer reduces packaging waste by harvesting “on-demand” and packaging his lettuce as a potted plant.
What Differentiates Vertical Farming Systems?
Vertical farm systems vary tremendously. These farms tend to “evolve” according to the farmer’s needs, capabilities, and available resources. Visual Capitalist has a great infographic on some of the commercial systems in operation.
The type of vertical farming, or the system of vertical agriculture, is the result of two critical factors:
- The physical layout of the farm and location
- The nutrient delivery system
Two other crucial elements to vertical farming include:
- The lighting
Vertical farming systems vary according to these elements; however, many other factors at work contribute to how a vertical farm operates, including the type of crop grown, the market you supply, and the size of the enterprise.
The Physical Location And Setup Of The Vertical Farm
Unlike traditional farming, vertical farming is not limited to a particular piece of land or resources.
Vertical farming is often conducted in:
- Indoors, which includes warehouses and old buildings
- Shipping crates
- Greenhouses and tunnels
- Old mining shafts
Within these systems, the setup of the growing trays also varies. Farmers often grow crops in tiers starting at two and increasing up to the roof of large warehouses. Physical space is a significant limiting factor. Another method of growing plants is on wall hangings or other vertically inclined setups. Maximizing space usage is a critical part of this farming method.
The Growing Method/Nutrient Delivery System
The quintessential factor determining the type of vertical farm system employed is how you grow the plants. According to ATTRA Sustainable Agriculture, the three systems of growing are:
Aeroponics will most likely take over as the most used hydration/growing system in the future. In these systems, plants receive their nutrient-rich water in a mist (similar to how hydroponics works, but with up to 90% less water usage) with no soil.
Originally patented by NASA in the 1990s, they developed aeroponics to try and grow plants in space. Plants grown aeroponically also assimilate more minerals and vitamins than other systems. While aeroponics in vertical farming is still relatively foreign, the trend is catching on.
Aquaponics is another fantastic hybrid system, meeting two needs simultaneously. The fundamental idea behind aquaponics is using the nutrient-rich water that fish produce to nourish plants grown in tiers/growing trays or any other holder.
Specific nitrifying bacteria and other microorganisms convert fish waste (poop) into useful, essential nutrients for your plants to consume. In these systems, plants grow in soilless mediums. You apply the nutrient-rich “fish-water” as needed to water these plants.
The plants’ roots remove the nutrients from the water, returning to the fish tank to start again. The benefit of this system is you end up with edible fish and plants. Aquaponics in vertical farming works in the same manner as hydroponics. You apply water to the plant’s roots, they take up the nutrients, and the nutrient “free” water returns to the fish tank.
Aquaponics is not a popular method of vertical farming commercially. This bias against aquaponics is that there are more “links” in the chain to manage (which could potentially fail, grinding the process to a halt). Aquaponics is often used in small-scale vertical farming where the benefits outweigh the drawbacks, and management is easier.
You can check out this video for a quick explanation of aquaponics.
A hydroponics system involves growing plants in a soilless medium saturated at regular intervals with nutrient-rich water from a tank. This water is either in the plants’ precise amounts or the excess drains back into the storage tank.
Various methods for applying hydroponics include deep water, drip irrigation, ebb and flow, nutrient film technique, and the wick system. The application method you settle on depends on the type of plants, your physical setup, and your capital.
Drip irrigation is the most popular type of irrigation systems in vertical farming. The most prominent reason for this popularity is the system’s ease of use and “simplicity.” It is also a robust system where fully controlling the nutrients added, volumes of water, and troubleshooting are easier to find than the other methods.
Other Controlled Factors
Although the other critical elements play a significant role in how plants grow, they do not dictate the type of system used.
The Lighting And Temperature
Completely controlled lighting (in a building and lights work on timers). Most systems employ a fully controlled lighting system. This control allows you to regulate the lighting’s intensity, duration, and timing. Improving growth performance.
A mixture between sunlight and synthetic lighting. In greenhouses, grabbing as much benefit from the sun is important. Using the sun saves you some costs, but the life-giving solar radiation propagates plants far better than synthetic lighting.
Temperature control is a critical part of the process. When maintaining plants at a constant temperature, you extend the growing season indefinitely.
The Humidity Levels
Humidity is another critical factor when farming. Certain crops come from moist areas, and they suffer/struggle to grow in areas with drier climates. When controlling the humidity, you allow these plants to thrive where traditionally they would not. Many plants require higher humidity to germinate.
Part of humidity control is airflow control. Air pumps are a prominent feature of these farms, pumping and circulating air evenly amongst the plants inside. Along with airflow, some systems contain carbon dioxide pumps to enrich the air.
What Are The Benefits Of Vertical Farming?
Vertical farming provides us with a multitude of benefits, including:
- Reduced space requirements and more efficient use of available space
- More food per foot of space
- Less water needed 70 to 90% reduction than traditional agriculture
- Longer growing season
- No pesticides or herbicides are needed
- No fertilizers are needed
- Not soil dependent (i.e., not limited by un-arable land), arid areas and cities are now perfect food-growing areas
- Versatile styles, i.e., fit in as needed
- Temperature, humidity, irrigation, and nutrients are predictable, pre-determined, and not wasted
What Are The Limitations Of Vertical Farming?
Although vertical farming is beneficial in many ways, there are also several limitations and downsides to this agricultural development. These limitations and downsides include:
- Expensive to set up
- Heavily dependent on electricity
- Without automated systems, this type of farming becomes difficult/almost impossible
- Although growing vertically in trays results in more room per foot for plants, the overall production of a vertical farm is usually less than on a traditional farm
- The type of plant is limited. Taller plants are not practical as vertical space is limited due to growing plants in tiers/layers. Leafy greens are the most popular type of plant currently when vertical farming
- Pollination issues. These farms are inside, which means no crop-damaging bugs or useful pollinator species
Why Is Vertical Farming Important For Our Future Food System?
In our modern age, farming is no less critical. According to the United Nations, the human population is expected to reach 9.7 billion by 2050, and roughly 68% of them will live in the urban environment.
This exponential growth, coupled with the increasingly adverse effects of climate change, will strain agriculture. According to Grantham Center for Sustainable Futures, we have lost roughly a third of arable land due to urbanization, pollution, and other anthropogenic issues.
With these issues increasing, vertical farming is a strong solution to the problem. Through vertical farming’s reduced space requirements and the fact that you can grow crops in buildings, smaller vertical farms that supply food on the community level could meet the needs of surrounding communities.
Vertical farming is a great supplement to the mainstream agricultural practices, but it is not yet at the point where it will surpass traditional farming. We hope to feed the ever-growing human population by combining the various systems.
On What Scale Is Vertical Farming Possible?
Another fantastic benefit of vertical farming is that the extent of the operation is not limited to a particular size. I.e., vertical farming benefits the backyard subsistence farmer as much as it benefits the commercial, warehouse-sized farmer. Vertical farming can suit most needs, provided you have the capital.
Although still in its infancy stages, vertical farming holds tremendous potential as a future farming technology. By completely controlling the environment plants grow in, you can manipulate all essential growth factors a plant requires. Vertical farming is fantastic because it is versatile and “molds” according to your needs. While the prominent system is based on hydroponics, aeroponics may become the staple method of growing in the future.
Therefore, if you are interested in starting one of these farms, remember that the system you choose to install should benefit the type of plant you grow, the location you have to work with, and your budget. So what are you waiting for? If you have the empty vertical space, why not start your vertical farm today?