Originally, Brian Lynch was shooting for the stars. Literally.

Lynch studied aerospace engineering with a focus on robotics throughout college, going as far as to obtain his Ph. D. in the discipline from Carleton University in Ottawa. But his and his wife’s desire to start a family led him to look to Earth for a career vs. a professorship in the field. 

“I was doing part-time teaching and my wife and I decided to try and have a baby, and school contracts are not very reliable,” Lynch says. “I then came across Vineland.” 

Lynch joined the Vineland Research and Innovation Centre, based in Ontario, in September 2018. Although he does not have a background in horticulture, he says it was a “perfect” place for him to land because it allowed him to use his expertise in robotics to solve problems. 

“Even though Vineland was outside of my primary interest in space exploration, I thought it looked like a great place to work because I get the kind of environment I want to be in at a university, but with more behind it,” Lynch says. “I’m also one of these guys that sees something shiny and I get interested in it, so any project I work on I tend to get really passionate about it.” Right now, the something shiny is smart irrigation with other projects forthcoming. 

“I still dream of sneaking in a project looking into greenhouses on Mars or something like that, but we’ll see if I can convince my superiors,” he adds with a laugh.

What a robot can do for you

Based on his prior work with robotics, Lynch says that it’s paramount to make sure a robot (or any technology) works not just in optimal conditions, but also in non-structured or unfriendly environments. In that way, a project in the greenhouse has similarities to one in space or down in a mine.

“It’s a dynamic environment,” he says. “Plants are always growing.” For smart irrigation, Lynch says most of the group’s research began “a couple of years” before he joined Vineland and that it had been carried to a point where he could take the baton and keep it going. The original idea of it was simple: make irrigation more efficient.

“Growers have so much information that sometimes they don’t even realize they are using it to decide if, or if not, to water plants on a given day,” he says, noting that specifically applies to herbs and flowers grown in pots vs. plants grown hydroponically or in a vertical farm. “I’ve seen growers take a chunk of soil out, squeeze it in their hand and, if enough water drips through, then they know it doesn’t need any water. Or they just pick up the plant to see if it’s heavy or not (to see if the plant needs water). It’s a judgement call.”

Lynch calls that process “subjective” — leaving it up to factors like the weather, the grower’s energy level on a given day, or any of the several factors that go into making the decision to water or not inexact. Oftentimes, this can lead to overwatering for fear of not giving a plant enough — which can lead to disease and pest issues.

Smart irrigation counters this by using sensors stuck right into the soil to determine when to water or not. With sensor data — specifically soil moisture, plus environmental data that growers may already be collecting in the greenhouse — the decision can be made.

“The method we ended up going with is more about teaching, so learning a grower’s pattern with artificial intelligence,” he says. “When I talk to growers, I tell them that the system isn’t meant to tell you when to water the plants. It’s not us saying ‘we’ve made this set of equations and it’s going to check the sensors and decide.’ It’s actually just matching the grower behavior — essentially seeing the patterns in the sensor data and matching the growers’ decisions.”

The idea, he adds, is to combine the two sources to make the recommendation more precise.

“Whatever a grower decides, they are making ‘yes’ or ‘no’ decisions and they get recorded,” Lynch says. “And the sensor data is applied at the same time. You’re basically identifying patterns in the sensor data that link up to the ‘yes’ or ‘no’ decisions a grower makes.”

Lynch says this is done once or twice through different crop cycles to build a map between what the grower says and what the sensor says. In time, he says, this will improve data quality and make life easier for the grower.

Applying the data and the next steps

According to Lynch, there’s a treasure trove of data already being stored by many greenhouses today. For the purposes of his projects, temperature and humidity are the two data layers most useful and found universally in greenhouses that are utilizing sensors. Light is another data point that is often easily collected. There has also been some research done at Vineland into correlations between carbon dioxide (CO2) and electrical connectivity (EC) in the soil.

In terms of applying sensors, Lynch says there are some challenges. For one, in some bigger greenhouses, plants are placed on long benches that can have different needs on one end or the other. Airflow, he says, is one thing that can affect each plant differently depending on where it’s located — specifically on the edges.

“Sometimes benches can be tilted and that can be invisible to the eye, but if you run water down it, then you’ll see run in a specific direction, thus making some plants get more water than others,” Lynch says. “So what they showed us is that you won’t necessarily be able to get away with just a few sensors — you’ll need more to make the best decisions possible. And that starts to drive up the cost.”

Lynch notes that one of the biggest benefits of smart irrigation is to save growers money, specifically on labor. In one Canadian commercial greenhouse for instance, the system reduced water usage by 15% and saved $2,800 Canadian (about $2,184 U.S.) in labor costs per acre of greenhouse space. But if more sensors are needed — and one estimate called for up to 2,000 sensors to cover a medium-sized greenhouse space — then it becomes harder to justify the cost.

The next step, Lynch says, is moving towards using more of the data already collected by the greenhouse and developing a decision support tool for growers. This model would rely on hardware already in place in the greenhouse and use data such as humidity, moisture and temperature to infer the soil’s real-time water moisture level. That data then will be used to map patterns in the greenhouse’s climate and water conditions. And from there, this can allow a grower to make a detailed prediction on whether and when to irrigate or not. Done in partnership with Dutch company Lets Grow, this model also has the added benefit of not having to worry about sensors being knocked over and placed properly — leading to inaccurate data collection.

That model, though, is still being fully fleshed out and fine-tuned for wider use by growers. Lynch, in the meantime, will keep working to push it forward with the end goal of making growers more efficient.

“Every day can be a download of the previous day’s data,” he says. “Growers are busy and this is unfamiliar to them — so I get why this can be hard for some. But growers are capable. And they will buy and invest in technology if it will help them.”

Carts are now the standard plant handling device for many growers. They have proven to be efficient, versitile and require very little maintenance. They are available to meet almost all of growers’ needs from transportation, shipping, displaying and customer service. And they can handle almost any material — bulk, bags, flats, pots or nursery stock.

All greenhouse operations can benefit from carts. The savings in labor makes the payback very short. Each time a flat is handled by a worker, at least 3 cents is added to its cost. One to three handlings can be eliminated by loading the plants in the greenhouse, rolling or fork-lifting carts onto a truck and unloading and pushing the carts into the garden center. A typical multi-shelf cart holds 40 to 60 flats.

Keep them on level ground

Ramps with a slope no greater than 1:12 should be installed between greenhouses or work areas that are at different levels. And keep in mind that, the larger the wheel diameter, the easier it is to move a cart. It takes about 20 pounds of force to push a 1,000 pound cart on a concrete or asphalt surface and about 40 pounds on hard-packed gravel.

Transport carts should be designed with flexibility in shelf spacing. Shelves should be easy to add or remove to accommodate different sized plants. Some manufacturers offer folding or knock-down carts to save on back-haul space. In some, the shelves are removed and stacked onto one cart and the bases stacked onto another. In others, the shelves are removed and the rack folded to a narrow width. A 22” wide cart is convenient as it holds the standard flat and fits into narrow aisles in the greenhouse.

The easiest way to load a cart onto a truck is from a loading dock. The height needs to be compatable with the height of the truck body. Another convenient method is to install a hydraulic tailgate so that the carts can be loaded from an outside growing area or unloaded at a garden center that doesn’t have a dock.

Carts vary in price from $200 to about $500 for one that holds 50 flats. Extra shelves are $40 - $50. Used carts are available from some suppliers. Cart leasing is popular in some areas.

To prevent the loss of carts sent to garden centers, they should be color coded or have a laser-cut name tag. Some growers are now using bar coding or RFID (radio frequency identification) tracking that can identified and track down the location of the cart.

Racks are a lower-cost alternative to carts.

Racks can be made from steel or wood. Most of them utilize a standard wood pallet as a base with vertical angle iron corner posts and brackets for adjustable shelves. Adequate diagonal bracing is needed. Plywood is the common shelf material.

If your delivery area is nearby, racks are usually left at the garden center until the next delivery. For delivery to more distant locations, some growers use disposable wooden racks.

Racks also save the number of handlings if they can be loaded next to the growing area. They are usually transported and loaded with a forklift or fork truck.

To prevent loss, carts and racks should be color coded, have a laser-cut name tag or feature RFID barcodes.

Storage considerations

An area is needed to store carts and racks to keep them out of the weather. A hoophouse is used by some growers. It should be leveled and have a smooth, well drained floor and easy access. Loading time depends on the distance between storage and truck. The experience of the operator also affects loading time with some carriers. Based on a study I did for the Horticultural Research Institute a few years ago, the average time to pickup and load a cart is about 25 seconds plus travel distance at 2 feet/sec. Average. time to pickup and load a rack is about 50 seconds. plus travel distance at 2 feet/sec.

Carts make a great low-cost tool to reduce the labor and cost of plant handling. Their flexibility and long life can help all size growing operations.

John is an agricultural engineer, an emeritus extension professor at the University of Connecticut and a regular contributor to Greenhouse Management. He is an author, consultant and certified technical service provider doing greenhouse energy audits for USDA grant programs in New England. jbartok@rcn.com

Eric Rohloff is quick to say that he’s not a head grower, even though his responsibilities at Esman Greenhouse sound like the duties you’d expect in that position. Instead, Rohloff prefers the title of “Head Plant Manipulator,” because his job entails more than just growing plants for the wholesale operation. Overseeing everything from greenhouse structures to environmental controls to his small team of assistant growers, Rohloff manipulates the conditions to produce pristine crops of wave petunias and other premium annuals for garden centers.

“It’s never been my job to just grow plants,” says Rohloff, who joined Esman in 2000. “It’s taking care of the whole place — not just the plants, but everything around them.”

In fact, this diversity drew Rohloff to the industry in 1983. He started working for a greenhouse part-time while attending college to learn tool and die making and, later, mechanical engineering. Before he finished his engineering degree, he fell in love with the greenhouse business and turned it into a full-time career. He sees plenty of similarities between his mechanical mindset and his growing occupation, since he’s responsible for installing automated equipment, greenhouse structures, plumbing, heating and electrical systems.

“At a lot of places, the growers are just growing,” he says, “but if we come in on a Sunday morning and there’s no heat, it’s our job to fix it. So, I want all my people to know how to troubleshoot to make sure the crop is safe.”

Teaching growers to troubleshoot

Rohloff’s team consists of two assistant growers with little industry experience. To teach them how to troubleshoot plant issues, he walks the greenhouse with them weekly to observe not only what’s happening with the crops in their respective sections, but also what’s going on in the rest of the facility.

“I tell my growers to look for what’s different,” Rohloff says. “Sometimes plants let you know what they need, and sometimes they don’t tell you until it’s too late, but [you’ll know when] there’s something wrong. Try to figure out: Is it you? Is it your water? Is it your media? Is it the plants? Is it a virus or a bug issue?”

Rohloff asks a lot of questions to train his growers to observe plant cues and conditions, and to help them figure out which inputs need to be manipulated to keep plants healthy. However, he doesn’t expect them to have all the answers. He encourages growers to use Esman’s proprietary database that tracks every chemical and biological application for each crop, which provides a detailed picture of growing instructions, troubleshooting solutions, and mistakes to avoid.

The database allows growers to look up temperatures, growth regulation rates, watering levels and other applications from previous years. Rohloff also uses the data to calculate chemical usage, so he can save money by purchasing bulk orders in advance.

The database began as an Excel spreadsheet that Rohloff built into a mobile app called Pest Logbook around 2013. Now, he even offers it to other greenhouses through pestlogbook.com. “The app made it easy to retrieve data, because we have access to information on our mobile devices,” he says. “That’s a powerful tool for us to be able to see what we’ve done in the past, and that keeps us consistent.”

Automating manual tasks

Greenhouse automation is a key component of Rohloff’s plant manipulation tactics. Using his mechanical background, he installed hands-off boom irrigation, in-floor heating, and environmental controls at Esman Greenhouse.

“We have a lot of tools available to keep our environment consistent,” he says. For example, since the sun can be a rarity during winters in Kalamazoo, Michigan, grow lights help mitigate the environmental conditions that Rohloff can’t manipulate.

“Technology is a huge time-saver,” says Rohloff, 55. “It’s a blessing and it’s bad, too, because you’re always tied to it. Some people think you can’t get away, but it allows me to have peace of mind because I can make changes from my phone and not have to run up to the computer all the time.”

Owner Scott Esman is committed to investing in technologies to keep the greenhouse running as efficiently as possible. In 2016, Esman purchased the adjacent property when the neighboring greenhouse owner retired, and since then, Rohloff has been steadily updating the old facilities with more efficient systems and materials. Recent improvements include replacing lathe and plastic with aluminum and Lexan polycarbonate end walls, adding automatic roll-ups, and installing new sidewalks.

The extra space doesn’t just bolster Esman’s 10-acre production capacity — it also helps boost employee morale. “We made so many improvements last year, which not only helps our growers’ attitudes (by giving them better tools to do their job), but it helps the people pulling product also, because the sidewalks were too narrow before,” Rohloff says. “When you improve the efficiency, it makes everybody happy: The crop ends up better, and the people feel better.”

Photo © pixel-shot | Adobe Stock

I’ve heard a rumor that plants with darker foliage would be taking the spotlight in 2021. But I am not really seeing evidence of that in new plant releases or media. What I am seeing is that all things gardening are “in,” be it foliage, flowers or food. 2020 ushered in a huge influx of new plant and gardening enthusiasts. As an industry, it looks like we are going to hang on to most of these new hobbyists heading into spring 2021. With indoor and outdoor gardening being a bright spot for many during an otherwise dismal year, these new customers carry with them a deep thirst for more of everything we have to offer. Are you ready to deliver?

Trendy tropicals

The houseplant boom has fostered renewed interest in any and all tropical plants. Tropicals with fanciful foliage and bright blooms are making their way back out onto the patio and into the garden. With so many of us spending so much more time at home and in our gardens — no matter how tiny — creating a sense of lush coziness is trending. Just as caladiums have caught on as indoor houseplants, a variety of other classic indoor plants are migrating back out to the garden. If we cannot vacation in the tropics right now, we can at least bring a bit of the tropics home, right?

Large-leafed Colocasia, bird of paradise, bromeliads and bananas will find homes tucked into the garden during the growing season, then brought back indoors as houseplants during colder months. I also suspect some customers will be willing to use more tropicals as temporary seasonal annuals and repurchase them the following spring. Using tropicals in this manner is, of course, nothing new to us, but it is new to most of our new gardening enthusiasts.

Anthurium and Alocasia of all types are having a heyday. Both make fantastic additions to spring and summer containers or tucked into the garden in pots. When brought back indoors they are some of the trendiest indoor plants. I am loving the Coffee Cups and Heart of the Jungle Colocasia in the Proven Winners program. Coffee Cups will make a perfect indoor specimen as well.

Same space, more plants

Another trend I am seeing is the desire of both indoor and outdoor gardeners to really pack in as many plants with a purpose as possible to maximize their space. Lawns are shrinking as urban gardeners get excited about adding more food plants to their ornamental beds, as well as adding more dedicated vegetable beds and containers. This goes for perennials, and the tropicals, as well.

Be sure to communicate both indoor and outdoor growing information for trendy tropicals and edible plants.

Dense wild-like plantings that create a sense of privacy and make one feel surrounded by nature are beginning to dominate the gardening conversation. 2021 is not going to be the year for sparse planting designs that feature tidy plants surrounded by miles of mulch or rock. All these extra plants and vegetable gardening of course increase time spent outdoors and engagement with gardening. This is a good thing.

That said, our customers are not necessarily looking for more tedious garden “maintenance” tasks; they are looking for health and wellness. We will need to help them plant more without feeling overworked or burnt out on gardening too soon. Focus on plants that shine in their natural unsheared forms, as well as plants that don’t need a lot of water or fertilizer, for foundational plantings. A low-maintenance garden “skeleton” will allow your customers to have fun accessorizing with thirstier tropicals and edibles.

Tiny is big

Gardeners want to pack in more edibles too, but bigger is not always better to achieve this goal. Packing in as many productive food plants as you can, in a limited space, means you may have to grow smaller varieties. I have been pushing the need for dwarf vegetable and fruit varieties for a while — specifically for the indoor grower — but we are now seeing small edibles coming into their own on patios and urban vegetable gardens. Miniature tomatoes will become increasingly popular (especially once outdoor growers figure out how to keep growing them indoors), along with dwarf bush types of beans, cucumbers, zucchini, and peppers. Dwarf fruits, such as the new hanging basket blueberry Midnight Cascade, are a perfect fit.

Growing tiny might also be just what the houseplant doctor ordered for indoor growers whose collections of large aroids have them feeling a bit overwhelmed. Yes, many new plant parents are taking what’s called a “plant pause” ... meaning they are reducing their collections and postponing buying new plants. Do we want them taking a buying break? No, no we do not. So how do we help them? Tiny plant species can feed the need for keeping pace with plant collecting, without taking up much space, time or resources compared to average houseplants.

No matter which plants end up trending in your area, I think the most important takeaway for 2021 is that consumers want more plants; but they also want more plants that do more for them.

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