A Hydroponic-Agriculture Renaissance

Center-to-Plate Garden
Orange County Convention Center

In the 1950's the use of plastic proliferated throughout a wide array of industries. New technologies using plastic catapulted society into the high-tech modern world of today. Greenhouses along with hydroponic farming benefited from the new technologies and lighter weight, cost-effective plastic construction material.

According to The Hydroponics Planet The History of Hydroponics article, the use of low-cost plastic as a staple construction material allowed for the innovation of drip systems, improved irrigation, filters, water reservoirs, among other inventions. Thus, modern hydroponic farming emerged as a result of the newly accessible and low-cost plastic materials.

... and a hydroponic-agriculture renaissance ensued in commercial locations previously inaccessible to farms.

Hydroponics: history(1)
Derived from the Greek words hydro (water) and ponos (labor), hydroponics simply is a gardening method that does not use soil. William Gericke, a professor at the University of California in Berkeley coined the term in the 1920's.

Hanging Gardens of Babylon
source: Ancient History Encyclopedia

Though modern hydroponics emerged in the 1920's, hydroponic gardens were prominent in several ancient cultures. The Hanging Gardens of Babylon, one of the Seven Wonders of the Ancient World, built by  King Nebuchadnezzar II (604–562 BC) along the East bank of the Euphrates River used hydroponic principles. From several hundred years BC, Egyptian hieroglyphics portray plants growing without soil along the Nile River.

During the Aztec reign in Mexico, natives constructed chinampas, rafts built with reeds and strong roots, and loaded them with rich sediment from nearby shallow lake waters. Plants thrived on the rafts; roots absorbed minerals from the sediment and worked through the raft to the lake below for consistent food and hydration. In its prime, the chinampas fed a community of 200,000 inhabitants. Chinampas may serve as the earliest example of aquaponics, a combination of aquaculture (practice of raising aquatic animals) and hydroponics in a symbiotic environment.

In the 1500's, Leonardo de Vince wrote his profound deduction that is the foundation of modern hydroponics:

“To develop, plants need mineral elements that they absorb from the soil by means of water. Without water, the plants do not survive, even if the soil has the mineral elements they need.

Water is as if it were the soul of plants, as minerals are as if they were the soul of soil. If we could transmit to the soul of plants [the water], the strength of the soul of soil [the minerals], perhaps we would not need it [the soil] to make plants survive and multiply.

I believe that, in a future that does not belong to me, that [this] will be possible. So, it is advisable to add fertiliser and irrigate periodically the lands for us to get a healthy and productive plantation.”

Credited as the catalyst for hydroponics research and writing, Sir Frances Bacon's Sylva Sylvarum, a book on growing plants in an environment without soil, published after his death in 1627. Subsequently, hydroponics research grew in popularity.

Often referred to as the "Father of Hydroponics," John Woodward, an English naturalist, antiquarian and geologist, published his experiments on growing mint without soil in 1699. As the first documented hydroponics, Woodward's experiments mark the inaugural step in the creation of modern hydroponics.

In the mid-1850's, French chemist Jean Baptiste Boussingault discovered that plants do not absorb atmospheric nitrogen; the roots derive nitrogen from mineral-rich water in the soil. Thus, Jean Baptiste proposed what is now referred to as the Nitrogen Cycle, how the element circulates between the atmosphere, terrestrial, and marine realms.

Previously mentioned William Gericke, a professor at the University of California in Berkeley, coined the terms aquaculture and hydroponics. Additionally, in the 1920's Gericke famously grew hydroponic-tomato plants twenty-five feet tall. While Woodward is known as the "Father of Hydroponics," Gericke is known as the "Father Modern Hydroponics" and published the renowned The Complete Guide to Soilless Gardening.

Wake Island hydroponics
Source: HydroponicAdvantage

During World War II, hydroponics was used extensively to feed the troops in the Pacific and South Atlantic. The first commercial hydroponics facility was built on Wake Island, an atoll in the Pacific Ocean used for global-flight refueling. Produce grown in the hydroponics facility was used to feed passengers during the long trans-Pacific flights.

By the 1960's the first specific hydroponic system, Nutrient Film Technique (NFT), was developed in England by Allan Cooper. NFT systems use a growing tray placed at an angle with channels for the plant roots. A water-based nutrient solution constantly flows over the roots, providing nutrition and aeration. Water not absorbed by the roots is recycled back through the system with no water waste.

In the 1990's NASA developed aeroponics to grow plants in zero gravity during space missions. Rather than water flowing over the roots, a nutrient solution is sprayed onto the roots. Thus, NASA research was the foundation for new patented aeroponic systems. Aeroponics is considered a type of hydroponics.

Hydroponics: advantages
Though hydroponic farming has many strong advantages, one of the most impressive characteristics is the water-savings over traditional soil-based farming. According to a University of Arizona Department of Soil, Water and Environmental Science 2011 article:

A hydroponic lettuce system could use only 10 percent of the water needed compared to field-grown lettuce. Arizona uses about 70 percent of its water for agriculture. Theoretically, about 90 percent of all that water could be saved if every farm converted to hydroponics

Creative hydroponics design
at the Center-to-Plate garden

Space-saving is another practical attribute of hydroponic systems. Since water is the nutrient-delivery vehicle with no soil buffering, plants are easily placed closely together and may be vertically stacked. Thus, with creative design hydroponic systems can fit into a facility's nooks & crannies. For commercial installations, the close plant proximity produces larger harvests than with their soil-based counterparts.

Additionally, in hydroponic systems, crops mature from seeds to harvest in a shorter time frame. According to the Epic Gardening article, 7 reasons hydroponics wins, a head of lettuce grows from seedling to harvest in around a month in hydroponics compared to two months in soil.

Eliminating the use of "cides" (insecticides, pesticides and herbicides) is a powerful environmental advantage for enclosed hydroponic farming. By controlling the growing environment, weeds, insect pests and other soil-borne diseases are not a factor for hydroponically grown crops and the use of "cides" is not applicable.

Per The Hydroponic Planet article, is hydroponic food nutritious?, food safety is another advantage inherent with hydroponic farming:

By removing the soil from the equation, as well as manure-based fertilizer, hydroponic growing greatly reduces the risk of contaminated food making it to the supermarket. The reduced risk of contamination is one of hydroponics great health advantages over traditionally grown food.

Tomatillo blossom
Center-to-Plate garden

Another advantage of indoor systems is a year-round growing season and the ability to grow "out-of-season" crops.

Since many hydroponic farms grow food for local destinations, the food is fresher due to shorter transportation times and arrives with a lower carbon footprint. The current hydroponic-agriculture renaissance encompasses strong potential to increase food access in urban neighborhoods, especially those within food deserts.

Tomatoes, cucumbers, berries (e.g. strawberries, blueberries), leafy vegetables (e.g. lettuce, kale, Swiss chard, spinach), peppers, herbs, and spring onions grow well in hydroponic systems and represent the most common crops.

Hydroponics: challenges
Installing a hydroponics system requires an upfront capital investment. Additionally, ongoing constant monitoring by a manager trained in the system's checks and balances is necessary to maintain healthy operations.

Molly Crouch checks
the Center-to-Plate garden

As they run on electricity, hydroponic farms are vulnerable to power outages and back-up generators are recommended. If a power outage extends beyond the generator's capabilities, the entire remaining crop is lost.

Though free from weeds, insects and soil-born illnesses, indoor systems are vulnerable to water-borne microorganisms that may infest the system. Pythium (water mold) root rot is a common water-borne disease in hydroponic farming and can be difficult to control once plants are infected. According to the Urban Ag News article, Pythium root rot on hydroponically grown basil and spinach, careful attention to growing practices and sanitation procedures can limit this disease to an occasional annoyance rather than an annihilating nemesis.

When disease strikes a hydroponics farm, the entire crop is infected due to the circulating water feed and potentially lost, depending on the disease type and intensity.

Though overall hydroponic farming is void of fertilizers and the "cides," few farms pursue organic certification. Organic nutrient solutions often clump and clog the pumps; thus, the system requires constant monitoring to ensure consistent water flow. The risk of clogged pumps and losing an entire crop often does not justify the benefits of organic certification.

Despite the stated challenges, hydroponic farming is common place for local food production in a variety of environments, ranging from regenerative farms to public-school systems to convention centers. The following sections depict successful hydroponic operations discovered during Elemental Impact (Ei) Founder Holly Elmore's travels.

Hickory Grove Farm | KSU Field Station(2)

HGF Hydroponics Lab

In 2013 the Georgia Department of Transportation (GDOT) leased a 26-acre tract of land to Kennesaw State University (KSU) for farm use. Formally, the site was the GDOT cement-mixing site for nearby I-75 construction. Though not toxic, the Hickory Grove Farm (HGF) soil was severely compacted and devoid of necessary minerals to sustain a healthy soil ecosystem. In addition, stormwater flowed off the property, rather than hydrate the "dead soil."

Due to the deteriorated state of the soil, one of the first HGF structures built was the Hydroponics Lab, which housed a state-of-the-art vertical hydroponic system. With each plant watered individually, the periodic dry time emulated nature and prevented root rot often prevalent in hydroponic systems. Within the lab, the tomato, cucumber, and various peppers-crop yields were impressive. Planting was timed to generate crops within the KSU-class rhythm.

Lush lettuce in the
Hydroponics Lab

Originally, HGF served as as a laboratory for The Michael A. Leven School of Culinary Sustainability and Hospitality (CSH) with an active class schedule. To prepare the students with the necessary skills to evolve into valuable culinary and hospitality-industry employees, the CSH required 400 hours of work experience and 200 volunteer hours for program graduation. Thus, HGF was the recipient of a significant number of student-volunteer hours for farm work.

In October 2017, KSU announced the CSH would be phased out by spring of 2021 and was no longer accepting new students. Thus, HGF lost their steady stream of student-volunteer hours and the farm-labor budget, other than HGF Farm Manager Michael Blackwell. It was time to step back and evolve the farm's strategic-operations plan.

With limited farm labor, Blackwell immediately assessed how he could maintain crop production. A top priority was replacing the the original vertical-hydroponics system with a table-top system to focus on lettuce and reduce required labor. With the Hydroponics Lab's new system, lettuce grows from seeds to ready-for-harvest in six weeks, broken down into three, two-week stages.

HGF can easily produce 400 pounds of lettuce per week, more than KSU Dining Services uses, even when at  full capacity feeding 6,000 students per day. Thus, Blackwell experimented with growing herbs and other produce in the Hydroponics Lab.

Italian parsley and Swiss chard
thrive in the hydroponics system

Effective July 1, 2019 the KSU Office of Research took over HGF management and renamed the farm the KSU Field Station. According to KSU Vice-President for Research Phaedra Corso, “The KSU Field Station is a valuable resource with endless possibilities to study how to protect and conserve our environment through different disciplinary lenses. We look forward to exploring new ways to make this Field Station a more integral and collaborative component of the KSU research experience for faculty and staff.”

The Hydroponics Lab is integral to the farm's new life as the Field Station and will continue to grow quality lettuce, herbs and other produce for KSU's stellar farm-to-campus dining program. Under Blackwell's leadership, the Field Station may integrate technology with regenerative farming practices to grow local, nutritious food in a cost-effective manner. By example, the Field Station may showcase how to prevent and/or repair urban-food deserts.

Blackwell substantiates the Field Station's important contributions:

“Through our work, not only are we demonstrating how to efficiently grow food in environmentally friendly ways, but we are also offering opportunities for KSU students and faculty to study the different biological and ecological systems so that we can be responsible stewards for our planet’s future,” 

The RiA Magazine article, Success is not static: evolution is required to create and sustain regeneration, details HGF's evolution from a campus farm to a research-field station. In addition, the article features the Georgia Institute of Technology sustainability team's visit to the farm as well as to KSU Dining Services.

An on-line version of the 2017 Southern Farm & Garden fall issue seven-page, multiple-article feature, the Ei Digital Book, Regenerative Agriculture Revives Soils & Local Ecosystems, showcases the incredible transformation of a former cement-mixing site into a regenerative farm. Holly provided the copy and photographs for the publication feature.

Spartanburg County Schools District Six

SCSD6 Hydroponic Greenhouse

In 2014 Spartanburg County Schools District Six (SCSD6) made a commitment to serve their students healthy food and brought food-service operations internal. Travis Fisher was hired as the Director of Food Services to oversee the culinary operations in the fourteen cafeterias as well as the catering operations.

SCSD6 SUCCESS: as shared in a WYFF July 2015 news report, SCSD6 served 38,000 more breakfasts, 106,000 more lunches, and 9,000 more dinners in the first year of serving healthy, from-scratch food to their students.

A natural extension of a healthy-food program is a farm-to-school focus supporting local agriculture. In 2016, SCSD6 evolved the farm-to-school focus to a campus-to-cafeteria endeavor with the construction of a greenhouse on the backside of the Dorman Freshman Campus. Buttercrunch lettuce, other lettuces, and herbs are grown in two different hydroponic formats for delivery to cafeterias.

SCSD6 NFT table-top system

In order to demonstrate diverse hydroponic/aeroponic growing techniques, SCSD6 first installed aeroponic tower systems and more recently installed a NFT tabletop-hydroponic system. SCSD6 learned the NFT system is much easier to monitor and maintain than the aeroponic towers.

At current capacity, the SCSDG greenhouse may grow 2,565 plants at any given time; each of the three aeroponic towers holds 675 plants for a total of 2,025 plants while the NFT systems grows up to 540 plants. At this juncture, 100% of the hydroponic-grown lettuces and herbs are destined for district-student dining.

SCSDG Director of Food Safety and Sustainability Patricia Tripp confirms food safety is a top priority within the district's commitment to serve healthy, nutritious food to students:

Growing hydroponically in a greenhouse allows the district to: 1) Grow year-around; 2) Grow in a sterilized medium that holds water and nutrients close to the roots of the plant; 3) Nurture the plants and students in a controlled and comfortable environment while providing a high-tech agriculture education. 

Aeroponic towers at SCSD6

The hydroponic greenhouse was a perfect step in SCSD6's evolution of the campus-to-cafeteria commitment to the recently launched Farm 2 School program.

In 2016, SCSD6 took possession of the 16-acre plot of land destined for the district's organic-certified farm. For the first year, farm staff tested the land to determine what could be grown crop-wise and officially opened as an operating farm in 2017. The SCSD6 Farm at Cragmoor is the foundation for creating a hyper-local food system for SCSD6. Even with the farm fully operational, all lettuce is grown within the safety of the hydroponic greenhouse.

The RiA Magazine article, Spartanburg County School District Six: a culture of EXCELLENCE!, gives an overview of the impressive school district and introduces the Farm at Cragmoor. The Ei FB album, Spartanburg County School District Six, is a pictorial recap of SCSD6 Farm at Cragmoor tours along with greenhouse images.

Center-to-Table Gardens

Center-to-Table open-air
aeroponic garden

Though commercial hydroponic gardens are generally enclosed in greenhouses, public facilities and schools often install open-air hydroponic systems for educational purposes. In addition, the open-air gardens provide ambiance as well as substantiate the facility's sustainability commitment.

Orange County Convention Center (OCCC), the second largest convention center in the nation, walks the sustainability talk with their Center-to-Plate gardens. Operated by OCCC food-service contractor Centerplate, the open-air hydroponic gardens are located in the Westwood lobby and greet convention attendees with a cheerful, sustainable welcome.

Opened in late 2016, the Center-to-Table Gardens were named the 2017 Outstanding Sustainable Program winner at the annual U.S. Green Building Council (USGBC) Central Florida region's LEEDership awards.

OCCC Sustainability Manager John Roberts substantiates the empowering message the Center-to-Table gardens give to arriving guests:

"Located immediately inside the main facility entrance, the Center-to-Plate Gardens welcome guests to the convention center via a wall of beautiful green foods; lettuce, kale, basil, scallions, mint. Strategically, guests ride alongside the gardens as they travel to main center levels. The gardens serve as a gateway into the myriad of sustainable experiences commonplace at the OCCC."

Colorful sprouts in the
Seedling Propagation Area

Toxic-chemical-free fruits, vegetables and edible flowers are grown from seed in the Seedling Propagation Area. Once mature, the saplings are transferred to the aeroponic towers to flourish until harvest. Urban Smart Farms manages the 2,000 square foot gardens, consisting of 81 aeroponic towers in two displays on opposite ends of the lobby.

With 44 planting spots per tower, the garden capacity is 3500+ concurrent plants. Planting is staggered to provide a consistent crop harvest. Delivered to Centerplate's kitchens, harvested crops are prepared for service to the convention center guests.

The onsite gardens allow Centerplate Executive Chef James “Chef K” Katurakes and his team the ability to use hyperlocal ingredients to increase the overall “Fresh from Florida” focus at the OCCC. Growing fully mature plants in 30 days also adds to their culinary creativity. At a fall 2018 event in the garden area co-hosted by OCCC and Centerplate at the UFI Sustainability Summit, the Global Association of the Exhibition Industry, a featured menu item was a small-plate salad composed of baby oak leaf lettuce hearts from the Center-to-Table Gardens.

OCCC - Centerplate Director of Sustainability Molly Crouch emphasizes Centerplate's strong support of and partnership with the OCCC on environmental commitments and endeavors:

John Roberts & Molly Crouch
in the aeroponic garden

Centerplate is a proud sustainable partner with the Orange County Convention Center (OCCC) in Orlando, Florida. The OCCC continues to raise its commitment to the environment through waste diversion, energy efficiency, community service, and local purchasing/sourcing including hyperlocal sourcing through its onsite Center-to-Table Gardens managed by Centerplate and its farming partner Urban Smart Farms.  

By having such a strong relationship with the OCCC, Centerplate is able to expand its own sustainable initiatives while working in congruence with the Center's goals. Centerplate looks forward to partnering with the OCCC for many years to come and continuing to advance sustainable programs and policies.

In September 2019, Molly hosted Holly for a photo shoot of the impressive aeroponic gardens and propagation area. The visit was also a follow-up meeting for the Ei Three-Step Straw Initiative.

The Holly Elmore Images FB album, Hydroponics Farming, showcases tours of the three featured commercial-hydroponic applications.

With the global population and desertification escalating along with a diminishing clean water supply, hydroponics farming holds promise to feed the world's citizens with healthy, nutritious food produced in a cost-effective and water-conscious manner.

... and remember relatively low-cost, lightweight commercial-grade plastic is the workhorse within the hydroponic-agriculture renaissance.

Resources:
(1) The Hydroponics Planet article A Brief History of Hydroponics by Oscar Stephens was the primary resource for the History section.

(2) Quotes and information relating to the KSU Field Station were obtained from the July 17, 2019 KSU blog post, Office of Research manages sustainable farm renamed KSU Field Station.