Aaron Bivens initially got into horticulture because he loved plants, but stayed in it because of the people. As head grower at Altman Plants’ Colorado Division and head grower captain for Altman’s entire operation, Bivens combines his passion for gardening with his penchant for teaching.

“It’s a blessing to have this career because I just love plants. That’s what keeps me passionate about [this job],” Bivens says. “But day to day, it’s really the relationships. You get to see employees develop and become better growers, and that’s my favorite part.”

Here’s how Bivens keeps Altman’s growing team on the leading edge of plant production.

Farm raised

Bivens grew up on a farm in northern Illinois, where his family raised corn, soybeans, pigs and cattle. He spent summers baling hay, while helping his mom tend a garden full of everything from pumpkins to petunias.

He started college as an education major, but soon realized how much he missed growing and switched to horticulture. He earned an associate degree of applied science in greenhouse and nursery management from Kishwaukee College in his home state, and then pursued a bachelor of science in general agriculture from Oregon State University.

After an internship at PanAmerican Seed, Bivens gained several years of head grower experience at Tanasacres Nursery in Oregon. That prepared him to start his own nursery in Oregon where he sold plants to independent garden centers, farmers markets and local grocery stores for several years, until the economic decline shuttered his small business.

Bivens worked at Smith Gardens for a few years until the Altman family recruited him — first for their Salinas, California, facility, and then he moved to Peyton, Colorado, in 2015. There, Bivens oversees the 32-acre growing operation from propagation to finished material.

“I call myself a grower, but I don’t really grow anything,” he says. “I orchestrate the growing operation through coaching, guidance, protocols and training. Most of my time is spent organizing and planning to see how everything pieces together in the big picture.”

Photo courtesy of Aaron Bivens

Scouting for issues

Bivens’ growing team in Colorado consists of five section growers, each with their own assistant grower, zone irrigators and labor leads, as well as a propagation lead and other specialized positions. At peak, it’s about 65 employees.

“I don’t have the ability to meet with 60 people every day,” he says, “so I try to focus my time with the supervisors to streamline communication.”

Bivens walks every zone at least once a week with each section grower to discuss their priorities. “We use a color-coded flagging system, so if something needs to be moved, it gets a red flag. If it needs to be pinched, it gets a purple flag. If it needs a drench, depending on the rate, it gets a different color flag,” he says. Those color-coded tasks keep growers busy while Bivens moves on to other sections.

Regular scouting is vital, in Bivens’ opinion, as it dictates his approach to pest control. With people on site up to 20 hours a day, “spraying to control pests and restricting people from entry into greenhouses can be challenging,” he says. “So, we’re looking at biological pest controls and softer chemistries.”

Since Bivens came to Colorado, he has introduced nematodes and pathogenic fungi and, more recently, persimilis for spider mites and cucumeris for thrips. After a successful trial with these beneficial bugs last summer, he’s been expanding the program. “Using predatory mites seems to be very effective from the standpoint of safety, but also efficacy,” he says.

Cultivating a team

In addition to overseeing production in Colorado, Bivens also serves as head grower captain for Altman’s whole operation. He spends about 20% of his time working with the company’s other head growers to share best practices and maintain consistency.

“The idea is to be someone they can use as a reference or a resource,” says Bivens, who runs a monthly crop protocol call and frequently travels to other locations in Texas and California. “We’re spread out so much across the country that we have to get communication flowing from site to site.”

As much as Bivens loves plants, his role has revealed that his true passion is coaching other growers.

“One of my favorite things to do is to teach people,” he says. “I think it’s important for people to understand why we do things, not just how to do them. So I try to explain why we use this fertilizer versus that one — not just from the standpoint of ‘this one makes it grow more,’ but, ‘this has high or low phosphorus, so this is going to raise or lower pH,’ — constantly trying to reinforce the science.”

But as imperative as technical knowledge can be, Bivens doesn’t want employees to lose sight of the real reason behind their work.

Above all, Bivens says, he’s “trying to instill ownership and pride in the crop. It’s cool to remind your employees that all these poinsettias are going to be on someone’s table for Christmas dinner. It gives value to the job.”

The author is a freelance writer and frequent contributor to Greenhouse Management magazine.

Sunlight is free, but it’s not always available in the amount greenhouses need it. To compensate, many growers install supplemental lights. Now, research shows that dimming lights based on sunlight levels can optimize crop growth and save growers money.

Marc van Iersel, professor of horticulture at the University of Georgia, is conducting research in this area. He also started his own lighting control company, Candidus, to help growers with dimming and other lighting needs — both with LED and HPS lights.

Greenhouse Management recently caught up with van Iersel to speak about light dimming best practices and the latest in lights.

Greenhouse Management: Broadly speaking, how can dimming lights help ornamental growers?

Dimming and taking advantage of the dimmability of LEDs can help in making sure that you provide light in the amount that the plants can efficiently use when they can best use it. So, when you’re growing in a greenhouse, you constantly have changing levels of sunlight and supplemental light is used much less efficiently when you have a lot of sunlight. By measuring how much sunlight you have and making the LEDs respond to that, you can make sure that you don’t provide light when the plants cannot use it efficiently.

GM: From a daily light integral (DLI) standpoint, do you have any general figures or ranges for when additional light is no longer beneficial to plants? I know it varies by species and variety.

MvI: That’s really hard to say. One thing that we have found — and this also ties in with dimming LEDs and controlling them — is that DLI by itself may not be all that good of a guideline. We are growing Rudbeckia seedlings in the greenhouse right now, and we’re doing that with different photoperiods. So they all get the same amount of light over the course of the day — they all get 12 mols — but it’s spread out over times, I think, ranging from … 13 to 22 hours. So if you give the plants the same amount of light but you spread it out over a longer period, then you get a lot more growth. That also has the advantage that from a practical perspective, you don’t have to install as many lights. So, it decreases the capital expense.

GM: How does dimming ensure that plants get the same amount of light every day? Does the amount by which lights need to be dimmed depend on how much sunlight there is?

MvI: The dimming that we do is always in response to sunlight, but we do it in such a way that by the end of the day, the crop receives ... a specific daily light integral. But through the algorithm that we use, we make sure that that light is provided preferentially when there’s little sunlight and the plants can use that light most efficiently. One really big advantage of this precise control of lighting is that it makes production more predictable. And since in our industry, almost everything is grown based on a contract with a specific shipping date, if you know that you have good control over the environmental conditions, it becomes much easier to make sure that your crop is ready when it needs to be ready.

GM: You started a new lighting company, Candidus, with Erico Mattos, a recent PhD graduate of UGA. What is Candidus and how does the technology work?

MvI: Candidus makes lighting control systems. We don’t make lights because there are plenty of other companies that do that much better than we ever could. So, what we do is we interface with existing lighting systems. We have a really simple interface for growers where they can set the photoperiods [like], when do the lights come on, when do they go off, what daily light integral do they want? Then, our control system takes over from there to make sure that those goals are achieved. So, our initial setup was designed for dimmable LED lighting systems, but right now we’re also working on systems that can do the same with high-pressure sodium lights or non-dimmable LEDs.

GM: With Candidus, can different sections of a greenhouse be dimmed at the same time?

Yes, you can have different lighting zones.

GM: Did you say you’re looking at dimming high-pressure sodium lights as well?

MvI: No, we wouldn’t dim them, but we would turn them on and off. Some high-pressure sodium lights have some dimming capability, but it’s not like with LEDs where you can dim very precisely and immediately.

GM: In addition to the research that’s available now, what more do you think needs to be done to ensure that growers provide their plants with the right amount of light and the right types of light?

MvI: What I would really like to see — and we’re working on — in addition to having a lighting system is to have some kind of imaging system that can actually monitor how fast a crop is growing. So then you can use benchmarking techniques where you know that after 25 days, your crop should have reached a certain stage. And, if for some reason, your crop hasn’t, then you can adjust the lighting [and] environmental conditions to help that crop catch up.

GM: Is there anything else you would like growers to know about light dimming and how it can help them in their production?

MvI: I think the big advantage of dimming [lighting] systems is the predictability [they provide] and providing light when plants can best use that light. So there are energy savings associated with it as well as the big benefit of making your production more predictable.

You may have heard that Proven Winners has decided not to participate in the 2020 California Spring Trials. Many comments I’ve seen following the announcement express concern over the future of the event, given this exit, as well as declining attendance. What does it mean for the event and the evolution of other plant trial programs and events around the country? 

I have a special place in my heart for plant trials. When I arrived in Dallas in December of 1998, one of my first major goals for my new job at the Dallas Arboretum and Botanical Garden was to build a plant trials program. That I did, from the ground up — from building the actual trial garden to developing the plant evaluation system to begging everyone I knew to donate free trial plants. I also worked on the Texas A&M CEMAP and EarthKind trials and established the North Texas Winners Circle with Brent Pemberton at Texas A&M, Overton. Within about three or four years, we had a sustainable program rolling along, including an All-America Selections (AAS) Trial Garden. These trials are still going strong today. 

In the years since, plant trial programs across the country have evolved in scope and grown beyond the traditional public and university garden borders. Many industry growers have created their own trial programs, realizing the benefits of on-site testing. Ultimately, all gardening is local; plants that work in Portland can’t be expected to work in Dallas. Unbiased comparative trials from public institutions and organizations are always going to be high-priority; but there’s no denying that trialing and comparing your own plants in-situ has strategic value. 

When it comes to how plant trial programs should further evolve, I’d love to see more focus on the benefits of plants to wildlife and food production. Beyond beauty, we should be testing for expanded plant value. An important testing metric should be to test if selected hybrids have equivalent food value to local insect and bird species or can host and provide resources to other local wildlife. What about soil improvement? I’d love to see trials on ornamental plants that also have a positive impact on soil quality. 

Despite my hands-on experience running plant trials, I’ve never once been to the California Spring Trials event. Crazy, I know. Neither the budget nor the time was ever available for me to do so at the time and March is the full swing of spring craziness here in Texas. Leaving town for a week during the peak of the season was simply a no-go. That said, I was immersed in technology back in the day and built a dedicated plant trials website so our data could be shared with the industry. I also launched a plant trials field day at DABS to bring the industry to us. That was how I tried to stay connected and disseminate key trial information. Even so, getting the word out in a meaningful way was tough and exposure was very limited. You really had to visit in person to get good information.

Over the last decade, trial programs have gained much more industry and public visibility via our intense internet culture and ever-expanding social media outlets. Everyone along the entire plant supply chain can disseminate plant information globally and instantly whenever they want. It seems to me that easy online access to key data may have vendors dropping out and attendants staying home, which makes complete sense. 

Travel hasn’t exactly gotten easier these days, nor less expensive. Travel also has plenty of negative environmental consequences and other impacts on resources. With more and more trade shows cropping up, there just doesn’t seem to be enough money or time to get to all the events one should. And let’s face it: many industry members, especially in the southern half of the country, can’t head out of state in March for any reason. There’s no doubt that seeing people — and plants — face to face has intrinsic value. Such events are valuable networking opportunities. But every business, and individual, must weigh those benefits against the costs of getting there and time away from the operations, especially in peak season.

For breeders and researchers hosting expensive trial events, producing better digital content may offer an improved ROI for everyone involved. If I’d had easy ways to upload video and images 20 years ago, I no doubt would have put much more effort into digital dissemination and kept on-site trial events a smaller local industry affair. Digital data, videos, images and social media engagement also give you the option to invite the public to join in on your content and learn more about plants that will work for them, not to mention drive foot traffic to public gardens who host accessible trial gardens.

With the ability to distribute high-quality visuals and data online, I suspect many in the industry will be rethinking how to both create and consume plant trial results — both to better use budgets and resources and be better educators. 

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Here are some of the top headlines you might have missed.

National Garden Bureau awards 2019 therapeutic garden grants

The first-place entry came from Magee Rehabilitation Hospital in Philadelphia.

After collecting thousands of votes from the public, the National Garden Bureau, American Meadows, Sakata Seed America and Corona Tools have announced the three therapeutic gardens receiving grants and in-kind donations totaling more than $5,000.

The three winning gardens are:

• Magee Rehabilitation Hospital, Philadelphia, Pennsylvania; First place vote-recipient; winner of a $3,000 grant
• Opportunity Knocks, Knockout Farm, Maywood, Illinois; Second place vote-recipient; winner of a $1,000 grant
• Wilmot Botanical Garden, Gainesville, Florida; Third place vote-recipient; winner of a $1,000 grant

Industry honors Dr. Paul Thomas through the American Floral Endowment

The dedicated professor’s legacy will serve as a scholarship opportunity for future students.

On Sept. 14, Paul Arthur Thomas passed away at the age of 65.

He worked at UGA for 29 years. Throughout his academic career, he impacted many lives: staff, students and many industry professionals across the horticulture field.

Per his obituary, he received numerous accolades through his distinguished career, including the Alex Laurie Award for Research and Education and D.W. Brooks Faculty Diversity Award.

A memorial tribute has been established with the American Floral Endowment (AFE) by the University of Georgia Department of Horticulture.

Bay City Flower Company to close after 110 years

The grower, based in Half Moon Bay, California, will shut down on Nov. 10.

After 110 years in business, Bay City Flower Company has announced that it will be closing on Nov. 10. 

“After four generations and 110 glorious years in floriculture, we at Bay City Flowers Company have decided that the time has come for us to wind down the selling of our flowers,” Harrison Higaki said in the release. 

The company was founded in Redwood City in 1910 by Nobuo Higaki, a Japanese immigrant who grew cut carnations, roses, chrysanthemums and gardenias in San Francisco, according to the company’s website. Bay City moved to Half Moon Bay in 1959.