In this issue, we’re once again trading some of the greenhouse photos for headshots as we honor seven people who are moving the produce industry forward, whether it’s promoting fruits and veggies on Capitol Hill or finding ways to produce better vegetable transplants in vertical farms. In our second annual People in Produce section, we feature an entrepreneur with a taste for unique crops, a scientist attuned to consumers’ sensory needs, a community-focused grower in the Arctic and more. Read about these interesting, successful members of the produce industry.

This month we’re also wrapping up our Urban Agriculture series with a feature on the economics of urban ag by Robin G. Brumfield and Charlotte Singer, both from Rutgers University. If you missed any of the other articles in this series, you can find them here. And if you’d like to improve your marketing, don’t miss Leslie Halleck's column this month about how interacting with your local area can strengthen both your relationships and your brands.

Christopher Currey takes a close look at tomatoes, the most popular crop among our readers, this month in the first part of a two-part Hydroponic Production Primer. He addresses some of the basics such as varieties, production systems, propagation and young plant production, and more.

For fertilizer best practices and the benefits of root zone oxygenation, you won’t want to miss the articles here and here that address these topics. Then, food safety expert Lisa Lupo offers advice on how to align hazards with risk when you’re developing your food safety plan, in order to remain compliant with the Food Safety Modernization Act (FSMA).

Finally, if you attended Cultivate’18 this past July, you may have seen the new vertical farm that popped up at the Greater Columbus Convention Center. Learn more about it and how it came to be in this month’s Consumer Corner.

kvarga@gie.net | (216) 393-0290

Twitter: @Karen_GIE

Photo: Adobe Stock

Making a good connection between what you sell, and why you sell it, and your target customer isn’t as easy as it may seem. When you’re passionate about what you do, make, or grow, it’s easy to get caught up in the idea that everyone else will be as passionate about it as you. It’s also easy to get a little judgmental about what you think should or shouldn’t be important to consumers. Even so, the market — and consumers — have a mind of their own. How confident are you that you and your ideal customer see eye to eye?

We don’t always need our customers to be as passionate as we are — and we don’t need them to be produce professionals. We just need them to be interested and have a need or a challenge. Then it’s our job to tap into that interest — spark it — and provide solutions. Meet the market demand where it matters. And yes, while we should be assertive about driving trends and staying ahead of consumer demand, we ultimately don’t get to decide what is or isn’t important to our customers, be it product or price. If you want more thoughts on this, check out my 2015 column titled “Prevent price prejudice” in Garden Center magazine.

While researching and writing my recent book “Gardening Under Lights: The Complete Guide for Indoor Growers,” I spent a lot of time digging into indoor gardening trends and the grow lighting market, as well as the demand for homegrown produce. Clearly, the manufacturing market for indoor growing gear has for a long time been singularly focused on one crop: cannabis. Recently, of course, that market has also evolved into intensive indoor commercial food production. This has left the rest of the mainstream gardening market a bit in the dark — if you will — when it comes to indoor growing.

Couple the stigma attached to marijuana with the lack of good indoor gardening education, and many gardening consumers have been left thinking indoor growing isn’t an option for them. Who wants to slink around a bookstore with a cannabis growing book when you really do just want to grow tomatoes in winter? Yet, hyper-local produce is in big demand and the desire for many consumers to grow their own produce is still on the upswing. I get tons of questions about growing crops such as herbs, tomatoes, and citrus indoors. Consumers want fresher local veggies, fruits, and herbs, and they’re willing to do a lot to get them — even without a yard or the sun.

Maybe not surprisingly, I’ve gotten a lot of pushback from green industry members about my efforts with indoor gardening: “Growing indoors isn’t logical;” “It’s too expensive and not efficient,” “It’s ridiculous to try and grow tomatoes indoors in winter;” “As growers we know you can’t generate enough light to grow fruits and vegetables;” — these are just a sampling of the comments I’ve received from professionals. To be frank, these comments are both judgmental and inaccurate. They seem to stem both from a refusal to accept that certain gardening and urbanization trends, as well as consumer desires, are changing — as well as an ignorance about current lighting technology — and perhaps a little fear of change. No matter the reason, we’re not being fair to consumers when we make these decisions for them based on our own personal feelings. The same goes for the type or source of produce they want to consume.

At a recent book signing event I did at a local garden center, one attendee came up and told me that she didn’t care if the indoor tomato she grew ended up costing her $64 — she just wanted to grow it. The act of growing that indoor tomato — even one tomato — was reason enough for her to invest in indoor gardening. That’s gold. Who are we to tell her she can’t even try? I know many people who spend excessive amounts of money on their boats, their vacations or their gun collections. Would we label any of these activities as efficient? Probably not. Are we going to tell these people they can’t have their boat, their vacation or their gun because it’s too expensive or inefficient? Unlikely. People will pay for what they want. Same goes for produce.

Plus, even with her $64 indoor-grown tomatoes in tow, that gardener is still going to buy tomatoes at the grocery store. She’ll probably buy fancier tomatoes, too, because now she knows more about tomatoes. We all win, because she’s engaging with her food and putting a priority on produce. The good news for the produce industry is that fresh, local food is on the minds of a lot of consumers. Engaging one-on-one with that food is becoming increasingly important to them: how and where it’s grown, how it’s prepared, and how it’s consumed.

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

Genetics: Microgreens are not classified by the species of plant produced; the term is simply a classification based on the stage the plant is harvested. Unlike leafy greens and herbs that are grown to finished-sized plants, when these species are grown as a microgreen they are harvested when their first true leaf is unfolded. Any species can be grown as a microgreen; production is based simply on the species having a desirable flavor and/or color. Many of the most popular microgreen species are in the mustard family (Brassicaceae), including arugula (Eruca sativa), radish (Raphanus raphanistrum subsp. sativus), mustard (Brassica juncea), kale (Brassica oleracea), and watercress (Nasturtium officinale). Other leafy greens such as Swiss chard (Beta vulgaris) are also used. Many culinary herb species are also popular as microgreens as well, such as basil (Ocimum basilicum), dill (Anethum graveolens) and cilantro (Coriandrum sativum).

Production systems: Microgreens can be successfully grown in a variety of production systems. One of the most common systems is very similar to the nutrient-film technique (NFT) system used to grow lettuce and herbs; the primary difference between those systems used for lettuce and herbs to those used for microgreens is the size of the growing channel. Channels used for microgreens are two to three times wider than the traditional 4-inch-wide NFT channel (Fig. 1). Another system that works well for growing microgreens is marketed for producing hydroponic fodder for livestock. The primary difference between traditional NFT systems and fodder systems is that there are multiple layers on the fodder system, while there is a single layer of channels on the regular NFT systems. These hydroponic systems utilize a fiber mat that comes in rolls or even burlap as the growing substrate that seed is sown into and grown on. Microgreens can also be grown in containers such as large open packs or flats filled with soilless peat or coconut coir-based substrates.

Propagation and young plant production: For microgreens production, propagation is essentially the entire production cycle, as they are harvested when the first true leaf is developed. All microgreens come from seed; there are no vegetatively propagated microgreens. An important consideration when sowing seed for microgreen production is the seeding density or the number of seeds per unit or area. Seeding density impacts microgreens yield; as the seeding density increases, the weight per individual plant decreases due to competition among seedlings, while the total yield increases from the increased number of seedlings in each area.

If seeds need darkness for germination, flip a black tray over the top of the flat or place a polystyrene board over the channel and remove once most of the stand has germinated.

Nutrient solution: Microgreens can germinate without any fertilizer application. However, providing mineral nutrients to microgreens will increase yields. Providing 75 to 150 ppm N from a complete, balanced, water-soluble fertilizer will enhance growth, though the concentration to use depends on your production system. For sub-irrigated systems like the NFT-like channels, use the lower range, while for microgreens that are irrigated overhead you can apply concentrations on the higher end of the range.

Temperature: Microgreens can be grown across a wide range of temperatures. Much of this is due to the wide range of plant species that can be grown as microgreens. Temperatures that are commonly used in greenhouse and controlled environment crop production work well, such as 68 to 72° F. While some species, such as many of the species from the Brassica family, can be grown at cool temperatures, the time it takes for seedlings to reach the marketable stage increases if grown too cool; warmer temperatures help your crops finish quickly and increase the number of crop turns in your facility.

Light: As evident when grown in multi-tiered hydroponic fodder systems, microgreens can be grown under low-light conditions since the seeds have stored energy they can use to germinate. However, microgreens will grow more and increase yields as light intensity increases. For greenhouse producers, supplemental light will only be required in the late fall, winter and early spring, when light is limiting. If you are growing in a controlled environment with no sunlight and rely on artificial lighting, it is not a matter of when you are going to provide light, but rather how much (the instantaneous light intensity).

CO₂: Like other food crops grown in greenhouses and controlled environments, microgreens are responsive to carbon dioxide (CO₂) concentrations. Supplemental CO₂ should be used in greenhouses when outside temperatures are cooler and venting is reduced, and can also be used indoors when necessary.

Pollination: Since culinary herbs are produced for foliage, not fruit, no flower pollination is required. Some herbs are produced for their seed, but they are produced in the field, not in controlled environments.

Pruning and training: Microgreens do not require pruning or training.

Pests & Physiological disorders: Due to the short crop time for microgreens, there are few severe pests or physiological disorders.

Diseases: The most significant disease in microgreens production is damping off of recently germinated seedlings. Seed can be sterilized prior to planting to minimize disease incidences.

Harvesting: Microgreens can be marketed in several different ways, either cut from the growing substrate and placed into a bag or container, or marketed while still growing in substrate. For microgreens that are sold “live” and attached to the substrate, the trays or growing units are simply collected from the greenhouse and, depending on whether they are sold wholesale or retail, they may be placed in decorative containers, then placed in plastic or cardboard carriers for transport and display (Fig. 2). For microgreens grown in loose soilless substrate and being harvested for sale, care must be taken so the loose substrate does not get mixed in with the microgreens shoots during harvest.

Postharvest care: While cut microgreens are protected when placed in a plastic clamshell, they are tender, and bagged microgreens are susceptible to bruising. For microgreens marketed in bags you should leave ample air that increases the size of the bag, like a brand-new bag of chips, to protect the fragile shoots. To maximize the shelf life of cut microgreens, place them in a refrigerator to keep them cool. It is difficult to recommend a single acceptable storage temperature because of the variety of species grown.

Most species grown will do best in temperatures in the mid-30s down to just above 32° F; basil is the most notable species sensitive to cold temperatures and should not be stored below 50° F.

Christopher (ccurrey@iastate.edu) is an assistant professor of horticulture in the Department of Horticulture at Iowa State University.

The brown stink bug (Euschistus servus) is a plant-feeding insect that can cause substantial damage to tomato fruit in greenhouses. Female stink bugs lay barrel-shaped eggs in groups of 10 to 25, usually on leaf undersides. Nymphs are wingless, brightly colored or multicolored, and round. Later in development, nymphs are less brightly colored and resemble adults. There are five nymphal instars. Adults are winged and shield-shaped, approximately 1/2 to 5/8 (1.3 to 1.6 cm) inches in length, with a distinct triangle on the back (Fig. 1).

Stink bugs primarily attack green tomato fruit but will also attack mature fruit. Adults and nymphs use their piercing-sucking mouthparts to feed on fruit (Fig. 2) and succulent plant parts like leaves and stems by withdrawing plant fluids. Feeding damage to mature fruit looks like pinpricks or small dimples (Fig. 3) that may be surrounded by a yellow or white halo. Fruit damage is caused by the removal of fluids from cells and the injection of digestive enzymes. Extensive feeding damage can reduce marketability of fresh market tomatoes. The brown stink bug overwinters as adults in crop debris or leaf litter.

Stink bugs can migrate from weeds located outside into unscreened greenhouses. Treatment with a contact insecticide registered for use in greenhouses and on tomatoes may be warranted when stink bugs are feeding on tomato fruit. The insecticide Azera [active ingredients are azadirachtin and pyrethrins (MGK)] is labeled for use against stink bugs in organic production systems. Consult your state or university-based entomologists for insecticide recommendations. Scouting will help detect stink bugs early in the cropping cycle and time insecticide applications. However, stink bugs will drop off plants when disturbed.

Raymond is a professor and extension specialist in horticultural entomology/plant protection in the Department of Entomology at Kansas State University. His research and extension program involves plant protection in greenhouses, nurseries, landscapes, conservatories and vegetables and fruits. rcloyd@ksu.edu or 785-532-4750