Safe, not sorry
Departments - Edible Insights
By Leslie F. Halleck
PHOTO: © freshidea | Adobe stock
Food poisoning is not something you wish on anyone. It's horrible, miserable and downright deadly. If you've ever had an E. coli or Salmonella infection, then you probably take food safety seriously. I know I do. Outbreaks of E. coli have plagued the field-grown leafy greens industry for the past three years in a row, with the most recent outbreaks sending romaine lettuce to the garbage bins across the country. With each recall, consumers are forced to focus more closely on where and how their food is grown.
With animal feces and surface water contamination for field-grown produce at the center of most of the leafy greens recalls, some food companies and restaurants are making shifts to buy from hydroponic and CEA producers. While this is a great opportunity for those of you growing under glass or in controlled environments, don't make the mistake of thinking that you won't come under the same safety and transparency scrutiny, or liability.
There are certainly many reasons why agriculture is making a big move indoors. It can be argued that CEA offers more local and sustainable food production, and that it requires less water than field growing and doesn't impact topsoil or lead to erosion. Controlled growing may also create conditions where fewer, or no, pesticides or herbicides are used. And when you're growing local, with potentially less pest pressure, you can grow edible varieties that offer up better flavor and nutritional value, versus having to grow varieties or use harvesting methods that cater to shipability.
While there may be a perception that the boundaries created by greenhouses or controlled environments mean safer produce, we all know that there are still plenty of ways contamination can happen. Growing in a controlled environment means you lose the benefits of nature's sanitizers: air and sunlight. Close monitoring of all environmental conditions is a must in hydroponics and controlled environments. Anywhere there is water involved, pathogens can spread. And of course, any time you have people involved in your production process, there's ample opportunity for all sorts of contamination.
With venture capitalists jumping into the CEA game, and new operations launching left and right, we can also argue that this is a very young industry with a lot of learning and growing to do. Mistakes are bound to happen. Many CEA growers may not even have a good understanding of what translates to safe, or not safe, growing or processing procedures. Technology is changing rapidly, influencing a variety of production techniques utilized differently by different growers. You do have much better opportunities for authentic transparency and traceability as a CEA, but collective standard protocols aren't yet where we need them to be.
This is a very young industry with a lot of learning and growing to do.
Enter, the CEA Food Safety Coalition (FSC). This new independent and member-governed organization debuted in 2018 and just recently announced the appointment of its first executive director. The goal of the organization is to bring together CEA growers of leafy greens to self-submit to external audits of their production processes. Then, thorough evaluation to develop appropriate food safety standards and consumer education.
If you grow leafy greens using any sort of controlled environment, be it hydroponics, aeroponics or aquaponics, and you're willing to submit to a third-party food safety audit, then you are welcome to join the CEA FSC.
If you grow produce, do you have a Farm Food Safety Plan (FFSP) in place? If not, it's time to get your house in order. You need to make sure you're keeping a detailed record of your operation's procedures and adherence to growing and processing safe greens or other produce. I suspect the CEA FSC will be working with members to develop FFSPs that help them fine-tune their safety measures and comply with federal regulations.
Good news if you'll be attending the United Fresh 2020 Convention & Expo, because they've just partnered with the CEA FSC to create a new Controlled Environmental Pavilion at the show. The Pavilion will showcase thought leaders and foster discussions between experienced and new growers, as well as highlight new technologies and food safety issues. If you're a CEA or service provider, you can now book booths both inside and adjacent to the Pavilion.
No one likes getting food poisoning, and we already throw away far too much food in this country. Growing as a CEA offers up the ability to not only limit waste of resources, but also produce safer and contamination-free food. Consumers are willing to pay you a bit more for your produce when you can be totally transparent about your methods and food safety concerns. But it's going to take a lot more research, learning, communication and community standards before CEAs can truly take the lead on produce safety.
Leslie (CPH) owns Halleck Horticultural, LLC, through which she provides horticultural consulting, business and marketing strategy, product development and branding, and content creation for green industry companies. lesliehalleck.com
United Fresh
Controlled Environment Agriculture
Ugly fruit
Departments - Editor's Letter
Kate Spirgen, Editor
It seems like out-of-the-ordinary produce is having its day in the sunshine. Long gone are the days when perfectly red, round (and often tasteless) tomatoes are the only options. Even here in the middle of Cleveland winters, we get heirlooms in different shapes and sizes. And for the first time this past Halloween, I saw Cinderella pumpkins and carnival squash. It made for some interesting Jack-o-Lantern options and some tasty side dishes.
And there are lots of other options on the shelves as North Americans whet their appetite for new types of foods. Options like tomatillos, habanero peppers, bitter melon and garlic scapes are becoming more mainstream to fit changing palates. Just take a look at a few popular recipe websites or social media channels and you'll see influences from all over the world in recipes that call for ingredients your grandparents would never have been able to find.
You may have also heard of the ugly food movement. In fact, there's a whole produce delivery company that has been making a lot of noise on social media lately. Imperfect Produce is making a name for itself by offering subscription boxes of different foods most grocery stores wouldn't carry. Some are nearing their expiration dates; some are oddly shaped and some are just surplus.
Their branding really speaks to the Millennial generation that's looking for ways to reduce waste (and their carbon footprints) by showcasing their mission to reduce waste. And by showcasing farmers they're helping and the meals they're donating, they're appealing to the younger generation's social conscience.
As out-of-the-ordinary and imperfect produce challenge the way North Americans look at their fruits and veggies, it could also open up some new marketing campaigns for your business. The unique is a little less scary than it used to be.
Kate Spirgen, Editor | kspirgen@gie.net | 216-393-0277
3 stories that shaped the produce market in 2019
Departments - Consumer Corner
The last calendar year featured another food safety scare, investment in local food and continued investment by several CEA operations.
Chris Manning
Photo: © SGr | Adobe Stock
In 2019, another E. coli outbreak hit the U.S., affecting field-grown greens. Last year saw more big news as more greenhouse operations in North America expanded. Retail chains also invested in locally produced food, banking on the trend to drive sales. These stories and others shaped the market heading into 2020.
CDC issues E. coli warning about romaine lettuce
In November, the Centers for Disease Control and Prevention warned consumers of an E. coli outbreak stemming from lettuce grown in the Salinas, California, region. It marked the second consecutive year where greens from the Salinas region were linked to an E. coli outbreak.
Following the outbreak, some CEA growers have marketed their product as a safe alternative to greens grown outdoors.
"The recall highlights the challenges and inherent food safety problems stemming from West Coast farming practices," Paul Sellew, president and CEO of New England-based Little Leaf Farms, said in a statement. "We're more certain than ever that our clean, sustainable greenhouse growing process cannot only ensure consumer safety but a fresher more delicious lettuce for the people of New England. We eat our salads to keep us healthy. We don't need to worry about them making us sick."
Kroger partners with Europe's Infarm to offer in-store living produce farms
In 2019, United States-based grocery retailer Kroger partnered with urban farming network Infarm to bring modular farms to some of its stores. Two stores — both in Washington state — will feature on-site hydroponic farms and offer greens produced in the store.
"Our partnership with Infarm allows us to innovate by combining ground-breaking in-store farming technology with our passion for fresh, local produce and ecological sourcing," said Suzy Monford, Kroger's group vice president of fresh, in the press release announcing the partnership.
Infarm, a startup based in Germany, has also built farms in Berlin, Copenhagen and London.
Mastronardi Produce made headlines in late 2019 by announcing its new facility in Oneida, New York, will total almost 3 million square feet — making it one of the largest greenhouses in the U.S. But they weren't the only business to add new space in 2019. Others include:
Little Leaf Farms beginning a 20-acre facility build in Yancey County, North Carolina
Canadian cucumber producer Big Marble Farms adding 10 acres of growing space, taking it to 45 acres of production
Fifth Season announcing plans to build a 25,000-square-foot vertical farm in Braddock, Pennsylvania, a historic steel town near Pittsburgh
Illinois-based hydroponic tomato grower MightyVine securing financing to expand from 15 acres to 30 acres
Bushel Boy Farms, based in Minnesota, spending $35 million to build a 50-acre facility for tomato production in Mason City, Iowa
BrightFarms announcing plans to invest $21 million to open a greenhouse in Hendersonville, North Carolina
It is unclear if the same level of growth will continue into 2020 and beyond. But 2019 showed that many operations are willing to spend money to continue growing their businesses and reach new markets.
Romaine lettuce recall
Mastronardi Produce
MightyVine
An automated workforce to harvest Canada's greenhouse cucumbers
Features - Production
Cucumbers are a significant export from Canada, but labor concerns are pushing growers to embrace automation.
Vineland Research & Innovation Centre
Editor's note: This story is part of the 2019-20 Innovation Report published by Vineland Research & Innovation Centre. The full report, as well as all past reports, are available here.
Due to a shrinking labor pool and rising labor costs, Vineland is working on a robot that can pick cucumbers in a greenhouse setting.
Photo courtesy of Vineland Research & Innovation Centre
Canadian cucumbers are a hot commodity. Canada is the world's fourth-largest cucumber exporter with a farmgate value of cucumber production at roughly $326 million in 2014.
Amidst this strong production outlook, human labor — both cost and availability — are holding the industry back. Human labor accounts for roughly 30% of total costs in cucumber greenhouses and harvesting — the most labor-intensive production task — accounts for roughly 20% of all work required to produce the crop. This translates into approximately $27 million spent annually on cucumber harvesting alone. This also has Canada's cucumber greenhouse operators looking toward an automated workforce of robots to maintain or increase production even as labor pools shrink and labor costs grow.
With help from Agriculture and Agri-Food Canada funding, Vineland's robotics and automation team is working to develop an autonomous robot capable of harvesting cucumbers in a greenhouse environment. By creating efficiencies and reducing labor costs, automated cucumber harvesting is expected to save a 40-acre operation roughly $1 million annually. The challenge is to develop a robot that can harvest cucumbers as well as, if not better than, humans.
"It is not just a matter of picking an individual cucumber — the robot has to do it quickly along a whole row," says Brian Lynch, Vineland's lead researcher on the project. "The robot must reach through vines to grab the cucumber, detach it from the vine and pull it back out (and not anything else), which is challenging for a robot. It wouldn't take much to snag a vine and drag down an entire row." To match the speed of a human picker, the robot needs to harvest one cucumber per second — all without causing damage.
Greenhouse cucumbers in Canada are typically produced using the "high wire" method, in which cucumbers are grown in a vertical, hanging configuration. Vineland researchers have been busy since 2018 visiting local greenhouses, trying to understand the nuances and challenges of harvesting cucumbers grown in this environment. The team has also started to build computer models on how high wire cucumbers grow, incorporating information such as where cucumbers are most likely to be found, their spacing and their ripeness.
Although the automated harvester is in its early stages of development, Lynch envisions a system that will deploy mobile robots mounted between rows of cucumbers in greenhouses. The robots would use a vision system and a series of complex algorithms to find and differentiate a ripe cucumber from surrounding leaves and vines, to reach out and grab it, harvest it, then place it into a collection bin.
Lynch's team has made the most progress on the computer vision system.
"We are starting to investigate using different sensors to look at color, infrared, 3D scanning and combining these to search for and locate a cucumber in an image, determine if it is ripe and calculate how far it is from the robot," Lynch says.
This is the type of information the robot will need to do its job. "By 2020, we will see the vision system come together and we will have results indicating it is working," Lynch says. The ability of the system to detect cucumbers at certain thresholds and levels of accuracy will be key measures of success.
Apart from its integration into the automated cucumber harvester, Vineland intends to commercialize the vision system as a stand-alone device.
"The solution we need to find cucumbers and characterize ripeness can easily be applied to any fruit or vegetable with enough water in it, such as tomatoes, apples or peppers," explains Lynch. In addition, "the applications of the vision system are also not just limited to harvesting," he says." The system can be used for crop monitoring, for example."
The Quebec-based National Optics Institute (INO) is an important partner in Vineland's efforts to develop the vision system. Once Vineland completes the prototype, INO will take it and make it work as a more commercial-ready product.
The design of the robot will be improved by 2020. The plan is to explore different robotic arm designs, as well as gripping and cutting strategies, to see which designs work best in a vine environment. A prototype that can reach out and pick a cucumber will be ready by spring 2020.
Understanding pH
Departments - Hydroponic Production Primer
In hydroponic systems, managing and understanding pH is essential to successful production.
Christopher J. Currey
Fig. 1. The chlorotic growth evident in these microgreens is the result of high pH, restricting micronutrient availability. Restricted micronutrient availability resulting from a high pH is one of the most prominent pH-induced disorders.
Photo courtesy of Christopher J. Currey
Managing the chemical properties of nutrient solutions and root zones is one of the primary activities in hydroponic crop production. Specifically, nutrient solution and substrate EC and pH are the two chemical properties most frequently monitored and adjusted. Understanding the fundamentals of pH — what it is, why it is important and how it changes — will improve the ability to manage it.
What is pH?
The definition of pH is the negative decimal logarithm of the hydrogen ion concentration. To simplify, pH is a measurement of hydrogen ions (H+). The negative decimal part of the definition relates to the counter-intuitive values. As the pH value goes up from, say 5.5 to 6.5, the concentration of H+ is decreasing, not increasing. Alternatively, as the pH drops from 5.5 to 4.8, the H+ concentration is increasing. The log-scale portion of the definition relates to the H+ concentration, where a pH of 5.0 has 10 times the H+ concentration compared to a pH of 6.0, and 100 times the H+ concentration compared to a pH of 7.0.
Above 7.0, the pH is considered "alkaline" or "basic" and the concentration of OH- is greater than H+. Alternatively, below 7.0, solutions are "acidic" and the concentration of H+ is greater than OH-. A pH value of 7.0 is neutral, where the concentration of H+ is equal to OH-. Although 7.0 may be considered "neutral", a pH of 6.0 serves as a better "center" for pH values for horticultural purposes, including hydroponics. A pH of 7.0, while neutral, is too high and undesirable. Broadly speaking, pH ranges from 5.8 to 6.2 or 5.5 to 6.0 are desirable for hydroponic nutrient solutions and substrates. That applies across most crops and production systems as well.
Why is pH important?
The pH is important for effectively managing mineral nutrition for plants. Nutrient availability changes as pH changes differently for the 12 essential macro- and micronutrients. The most pronounced effect of pH on availability is for micronutrients. Starting at a pH of 6.0, the availability of micronutrients decreases as the pH increases. Alternatively, micronutrient availability increases as the pH decreases below 6.0. This is the reason many plants develop interveinal chlorosis when the pH is too high (Fig. 1).
By maintaining nutrient solutions and substrate within the target pH ranges recommended for various crops, and specifically avoiding high pH, nutrients are kept available to plants and deficiencies are avoided. In order to maintain target pH ranges, recirculating nutrient solutions are constantly treated to adjust their pH. Acids are used to reduce pH, while alkali or bases are added to increase pH. Usually, substrate pH is maintained by adjusting nutrient solution pH for hydroponic production systems since nutrient solutions are applied so frequently and have a strong influence on substrate pH.
How does pH change?
There are several reasons why pH can change in recirculating nutrient solutions and hydroponic substrates. One of the causes of pH change is nutrient uptake. Roots need to maintain an electrochemical balance to properly function. Therefore, when a negatively charged ion is taken up, an OH- is released, whereas when a positively charged ion is taken up, an H+ is released. A good example of this is the nitrogen in fertilizers. When positively charged ammonium (NH4+) is taken up and an H+ is released, the pH decreases due to the increasing H+ concentration. Alternatively, when negatively charged nitrate (NO3-) is taken up and an OH- is released, the pH increases due to the decreasing H+ relative to the increasing OH- concentration.
In addition to nutrient uptake and conversion, root respiration also affects pH. Although roots of hydroponic crops don't photosynthesize, they do respire. As roots respire, oxygen is consumed and carbon dioxide and water are given off. The CO2 given off reacts with water to form carbonic acid and this, in turn, decreases pH.
While several factors can change nutrient solution and/or substrate pH, alkalinity in water also affects pH. Alkalinity is a measurement of the carbonate and bicarbonate in water. Ultimately, alkalinity acts as a buffer against pH change. Water with low alkalinity will result in nutrient solutions and substrates where pH can change easier. Alternatively, water with high alkalinity will inhibit nutrient solutions and substrates from readily changing pH.
The take-home message
One of the biggest benefits to hydroponic crop production is the precise control of water and mineral nutrition. The pH of your water, nutrient solution and substrate can affect crop quality. By understanding and anticipating potential pH effects, combined with proactive management, pH-related disorders can be avoided and productivity can be maximized.
The author is an associate professor in the Department of Horticulture at Iowa State University. ccurrey@iastate.edu