Karen E. Varga
Getting engaged. Having a baby. Buying a new home. Losing a loved one. These are all important moments in our lives, and we celebrate or mourn many of them with plants. The concept of connecting plants with life moments came up several times in this summer’s travels, including the European FlowerTrials, featured in our cover story this month.
At many of the stops, we saw this theme repeated in different ways. The most obvious example was at Florensis, where the entire stop was based around displays commemorating moments in the life of a 20- or 30-something fictional character, Fleur Longway, who even had her own Facebook page. Fleur had a tabletop “dream wedding” display that incorporated white calibrachoas and New Guinea impatiens, a sports area representing her hobbies, a landscaped cemetery plot giving a nod to those she’s lost and a showcase of the plants she’s put in the front yard of her first home.
I also saw this concept exemplified while in Denmark for the International Garden Centre Association Congress. We were at GASA GROUP, an international trading company that supplies European markets with floral products, where a wide variety of merchandising ideas and point-of-purchase options were on display. I chatted with one of their sales representatives, who told me that they develop some of these concepts with “life moments” in mind. For example, one collection was based around a “New Beginning” theme, while others focused on love and specific holidays.
The cover story in this issue is different than usual in that it incorporates perspectives on European FlowerTrials and other aspects of European horticulture from several women in the North American horticulture industry. I feel fortunate to have experienced this trip, organized by the all-women’s group Luxflora, and learn alongside these professionals for a week. Each woman had her own set of aspirations for the trip, from getting ideas for marketing materials to finding new plants to complement what they’re currently growing, but all of us came out feeling like we had not only learned a considerable amount, but also gained new friends. Turn to page 12 to read more about the trip.
What we call “Fusarium” is really many different diseases clumped under the name of a fungal genus. Both systemic vascular wilt diseases (Fusarium wilts) and a miscellaneous assortment of root and stem infections — even some leaf spots — are caused by Fusarium fungi. The root and stem problems are more common but less serious than the wilts. Fusarium diseases can have lethal consequences under conditions that favor their attack.
The host-specialized Fusarium wilt fungi each affect only one crop, or very closely related plants. Aster, basil, begonia, carnation, chrysanthemum, cyclamen, dahlia, gerbera, gladiolus, lily, lisianthus, Marguerite daisy, exacum, ranunculus and tulip all have a Fusarium wilt disease. Propagators make heroic efforts to keep Fusarium out of the chain of production with their culture-indexing, monitoring and sanitation measures. Cyclamen is especially hard to produce free from its Fusarium wilt because the pathogen is seedborne. Spread of Fusarium wilt fungi is most common through vegetative propagation. The more omnivorous root and stem rot Fusarium pathogens may be spread by movement of invisibly-infected plants or by soil contamination of a growing mix (by workers or insects).
The species of Fusarium that cause root rots and stem rots (such as Fusarium solani or F. avenaceum) are common soil dwellers, and tend to have wide host ranges. The Fusarium wilt pathogens, on the other hand, are closely associated with the crops they can parasitize, and are more likely to arrive as latent infections within the xylem of cuttings rather than being blown or splashed in from the environment. Once Fusarium wilt has occurred in your greenhouse the pathogen is very talented at surviving in crop debris or soil on the floor — so the threat of disease can continue if there are no effective sanitation efforts.
Fusarium root and stem rots can strike at any time. These attacks are helped by fungus gnats or cultural actions that injure roots or stems. Fusarium wilts often become more obvious during higher growing temperatures (summer).
Monitoring for disease
Check your crop’s root health regularly: irregular heights may indicate root rot or stem cankers.
Watch for lower leaf yellowing or wilting that might indicate Fusarium wilt in a crop known to be susceptible.
One-sided wilting or a dark discoloration of the vascular system are clues that may indicate a Fusarium wilt disease.
A lab diagnosis will help you to know which kind of disease you are fighting.
Monitor fungus gnats, which may spread Fusarium species, using yellow sticky cards (adults) or potato chunks (larvae).
Prevention of disease
Have impeccable sanitation in your greenhouse, cleaning especially after a disease outbreak.
Avoid overfertilization or overwatering, which will injure roots and provide entry for Fusarium fungi that cause root and stem rot.
Manage fungus gnat populations that could aggravate Fusarium problems.
Order from the most reliable suppliers when purchasing plants susceptible to a Fusarium wilt disease: purchase clean stock for any crop for which it is available.
Treatment of disease when present
Dispose of diseased plants promptly.
Chemical control is often inadequate, especially for the wilts. Materials that suppress Fusarium somewhat include azoxystrobin, fludioxonil, iprodione, pyraclostrobin and thiophanate-methyl, as well as some biological controls.
For vascular wilts, try growing at a high pH (6.2 or above) and with nitrate rather than ammonium forms of nitrogen. This cultural scenario strongly suppresses Fusarium.
Margery Daughtrey is a plant pathologist specializing in ornamentals at Cornell’s Long Island Horticultural Research & Extension Center. She aims to help growers outwit diseases.
Light-emitting diode (LED) lighting is growing in popularity and improving technologically as growers are trialing and implementing LEDs into their operations. Here are two recent insights and projects from two of the industry’s top researchers.
Part I of a two-part series. Next month, we bring you studies from Erik Runkle of Michigan State University and Cary Mitchell of Purdue University.
Controlling plant growth and behavior with light: a perspective
By Kevin M. Folta, professor and chair, University of Florida Horticultural Sciences Department
The magic in growing plants is that they do well with water, a sprinkle of critical nutrients and application of light. We usually associate light with the process of photosynthesis, and modern lighting regimes reflect this fundamental assumption. However, is simply providing photons to a plant necessarily the best way to support them, or maximize the value of plant-based products?
Light is not just the stuff that plants need to grow. Light is actually a mixture of information that can guide plant growth, development and productivity. Light is described by at least three parameters, including wavelength (color), fluence rate (intensity — sort of) and photoperiod (duration). Alteration of these variables can have a profound effect on plant biology, and plant product production. In nature, the relative amount of red, blue, green and invisible colors off the ends of the spectrum shift throughout the day and over a season. Some wavelengths tell plants about the position of neighbors or the density of vegetation.
We also know that different wavelengths have different effects on specific aspects of plant growth. In other words, when a plant cell in the leaf “sees” a blue photon, it provides specific instructions to the nucleus of the cell, changing which genes are turned on and off. Blue signals have been mechanistically linked to processes like bending toward light, production of purple pigments, control of flowering, leaf expansion and internode growth inhibition.
On the other extreme, the invisible light energies beyond the red end of the spectrum provide different information through a different cellular light sensor. Information through this pathway affects leaf angle, promotes internode elongation and decreases chlorophyll accumulation. These are just a few of the changes initiated by exposure of “far-red” light, and are mediated far-red specific changes in gene expression.
The blue and far-red examples are just two of the known effects of specific wavelengths. The last two decades of plant research has described specific effects of UV light, blue, green, red and far-red radiation. This range of sensors and responses poses an important question. If discrete plant processes are controlled by different wavelengths, could we mix light ‘recipes’ that allow the grower to not just grow plants, but rather, control the way they grow?
This line of thinking is growing in popularity as scientists and growers consider clever tricks that elevate opportunities beyond the solar spectrum. The possibility to literally control the way a plant grows or behaves without the use of chemicals and labor is an attractive one.
Research at the University of Florida, Purdue University, Michigan State and others has shown the exciting potential of the technology. Application of specific colors can change flavors, colors, size, fresh weight and a variety of other important qualities. Evidence shows effects on growing plants as well as the harvested products.
But are university growth chamber experiments industry scalable? It is becoming reality. Over the last two decades light-emitting diodes (LEDs) have replaced bulbs from our household fixtures to the streets of Las Vegas. Their long lifetime and low power profiles have prompted their rapid adoption. As these types of lights have become more commonplace we’ve observed two common trends — the lights get brighter and the costs get lower.
Together these two trends have growers considering LED-based fixtures for day-length extension and product improvement, either as a sole source or as a spectral supplement. At the same time, corporate and university research is defining new edges of the application, unveiling interesting new angles that can maximize the genetic potential for any given plant, or allow fine control of important processes like the timing of flowering.
Controlling how plants grow and behave means speaking to them in a language they understand. Manipulation of the light spectrum is a relatively untapped variable that is poised to make great contributions to growing plants in protected and controlled environments.
‘LED it be’: 50-percent energy savings may be possible by the smart use of LEDs in greenhouse horticulture
By Dr. Leo Marcelis, Wageningen University - Chair group Horticulture and Product Physiology
LEDs provide exciting new possibilities to modulate spectrum and direction of light, instantaneous control of light intensity, and the ability to separate lighting from heating. We just started a five-year research program called ‘LED it be.’ In this program, five Dutch universities and nine private companies (Philips, LTO Glaskracht, Nunhems, Bejo, Rijkzwaan, Plantenkwekerij Van der Lugt, Westlandse Planten Kwekerij, Hortimax, B-Mex) work together to fundamentally understand the responses of plant processes to many of the different features of light, and then translate this knowledge into management practices. The goal is to save 50-percent of energy output in greenhouse tomato production.
In the Netherlands, a tomato grower in a modern greenhouse with high-pressure sodium (HPS) lighting typically uses 3,100 microjoules (MJ/m2) of fossil energy per year, 80 percent of which consists of electricity for lighting (2,480 MJ/m2). The remaining 20 percent (620 MJ/m2) is mainly for heating and humidity control. Furthermore, 530 MJ/m2 of the lighting energy also contributes to fulfilling the energy demand for heating and humidity control.
The main obstacles to saving energy are in the departments of lighting and air humidity control. To realize an overall energy reduction of 50 percent, a 60 percent reduction of electricity use for lighting is required. Compared to HPS lighting, 30 percent reduction of electricity use can be realized by LED lighting due to a more efficient conversion from electricity to light. Improved light absorption by adapted canopy architecture and positioning of LEDs can save 15 percent electricity. This seems to be a realistic value if you consider that 5 to 7 percent of light from above is reflected by a canopy and 5 to 10 percent of the light is vanished unused in the floor. These losses can be reduced by interlighting. Furthermore, we calculated by a simulation model that adapted plant morphology can improve crop photosynthesis by 10 percent due to better light distribution. Diffusing greenhouse covers can increase crop growth by 5 to 10 percent, indicating that improving distribution of light absorption in a canopy is of great benefit.
Ten percent saving on electricity is expected to be realized by improved photosynthesis as the quantum yield of photosynthesis is spectrally dependent. Five percent saving on electricity is expected from improved assimilate partitioning.
We anticipate that more fruits will set and fewer fruits will abort, and that more assimilates (or sugars) will move out of the leaves into the fruit with the use of smart lighting. Furthermore, lighting will be used to enhance disease resistance of the crop and decrease transpiration at moments that transpiration leads to energy costs. The generated knowledge will be accumulated in a model-based management support system.
The program has just begun. At this moment, young plants of 40 different cultivars are grown in climate chambers under eight different light spectra. This serves as an initial screening of cultivars and light conditions for further research in this program.
There are multitudes of reasons for selling a business. But the common denominator in any sale is that it takes a lot of time and an exceptional amount of paperwork. This account follows Jim Snyder, a grower who spent five years planning the sale of his business. This was not, by any means, a so-called fire sale. And his advice applies only to the premeditated sale.
After nearly 25 years of operating Riverbend Nursery in Riner, Va. (which includes 460,000 square feet of heated and unheated indoor growing space, according to the business’ website), Snyder and his wife Julie started seriously thinking about their future. Did they want to continue to work in the nursery they built together six or seven days a week for years to come? If not, what would they do with some free time? After some serious discussion, the husband-and-wife team decided they wanted to generate some flexibility and travel extensively, Snyder recalls.
“So we started developing an exit strategy, and my goal was to slow my work pace by age 55 to do some traveling for months at a time,” he says.
The plan from start to finish took five years. Once the decision was made to sell, Snyder identified a group of key people to help answer questions.
“We did that five years before the sale,” he says. “In our case, it was a couple of people we knew who had already sold their businesses.”
Next they contacted attorneys, an accountant and a banker whose business they didn’t use for their nursery or personal banking. They also talked to people outside the industry about selling a business. Snyder also asked business brokers what they looked for in a business.
“I asked them, ‘What can I do today to prepare myself to sell in a few years?’”
For anyone in the preliminary stages of contemplating a sale, Snyder says to ask yourself, “Am I really committed to this?”
“It takes a phenomenal amount of work. It was at least two to three times more work than I ever thought,” he says. “Once the decision to sell was made and the broker was chosen, our broker asked a lot of questions and asked for a lot of financial background information.”
Selling a business is not as simple as turning over a few years of financials, he adds.
“First, you must put your financials in a clear, businesslike manner. The typical small- or medium-sized grower doesn’t necessarily follow general accounting principles. If that’s the case, you have to redo or reformat your financials into a known, understandable format. And that takes a lot of work,” he says.
He also suggests having a price threshold in mind.
“But you have to peel out the emotion from that process,” he warns.
Understand that it’s an emotionally draining process, he adds.
“It’s mentally, physically and emotionally draining, especially if you started the business or have been involved in it for a long time,” he says. “This process may nag at you because you’re doing things behind closed doors and not telling employees.”
At the beginning of the five-year planning and selling process, Snyder considered what would happen if a buyer wanted to keep him on as CEO.
“It’s important to a prospective buyer that the business stands on its own. But it’s also important to relay what you bring to the business if you stay on with the company,” he says.
Three years prior to selling, he made sure the business was in a position that was already attractive and marketable. For some sellers, that means changing your viewpoint on profitability, he says. It also means presenting the nursery’s point of differentiation, as well as proving that you have a strong staff.
Choosing a broker
About a year before the nursery officially went on the market, Snyder interviewed three or four brokers to handle the sale. He asked each of them to describe the primary buyer to which they market. He gave each prospective broker three years of financials and asked them to provide a fair-market value.
“We got answers all over the board,” he says. “One had some ag experience, but the operation was much larger and it was part of a distress sale. But they all looked heavily at our current earnings and our EBITDA (earnings before interest, tax, depreciation and amortization) and tried to project future earnings.”
After the interview process, Snyder gravitated toward a broker who asked a lot of detailed questions and “seemed like they truly wanted to learn about the nursery,” he says.
One of the biggest lessons to keep in mind during this process: The fee or the highest selling price are not necessarily the best considerations when choosing a broker.
What to expect
During the buyer’s due diligence, they examine everything.
“Be prepared to discuss things that could be uncomfortable,” he says. “Of course, if you’ve disclosed everything, you have nothing to worry about.”
Create an accurate asset list. Find contracts and titles. Document everything.
“A buyer can look at anything and say, ‘Prove it,’” he says.
Snyder says he can’t stress enough the amount of work and time it takes to sell a business. Also expect compromises throughout the entire process. There are a few things he says he wished he’d known from the beginning.
“The buyer wants to set up the sale for his tax benefits, and the seller wants to set up the sale for his own tax benefits. You must understand the tax implications going in to this. I wish I knew more about that when I started.
Ask an accountant and your attorney — ones who are well-versed in mergers and acquisitions. Expect lots of legal fees. And I wish I would have asked to look at a boilerplate of a typical seller’s agreement. I may have had fewer surprises that way,” he explains.
A done deal
Superior Street Partners LLC, a private equity firm focused on the lower-middle market, purchased Riverbend Nursery.
Snyder remained with the company as CEO after the sale. His role hasn’t really changed, although he’s transitioning away from the daily operational duties and direct reports and moving to the role of strategic vision and business development. He’s on the board of directors with three of the owners.
“The group of owners who purchased the company has helped me grow professionally,” he says. “They all bring business aspects to the table that I clearly didn’t have. I now have a wealth of knowledge to pull from.”
After the sale
Once the sale was complete, Snyder told the staff.
“We waited until the day we closed. We had a meeting and the first thing we did was apologize for not saying anything,” he says. “Then we explained that it wasn’t a fire sale and we laid it all out there. We didn’t lose one employee.”
Snyder enacted an appreciation bonus for anyone who stayed on for a year after the sale.
“We took some of our proceeds and invested them back into our staff because they helped build this business. They helped make this possible for my wife and I, and we want them to share in the happiness.”
Kelli is editor of Nursery Management magazine.
One of the key factors in optimum plant growth is providing adequate light for photosynthesis. During the summer, with long days and high sun angle, this is not a problem; however, during the fall, winter and spring, light levels are usually marginal. Add to this the loss of light due to greenhouse glazing and the obstructions in the greenhouse and the light that gets to plants is usually less than is needed for optimum plant growth.
The Daily Light Integral (DLI) was developed by scientists to provide a measure of cumulative photosynthetically active radiation (PAR) received by plants over the course of the day. It integrates light intensity in micro-mols per square meter per second (μmol/sq m-sec) and totals this over a 24-hour period. The total daily integral is expressed as mols per square meter per day (mols/sq m–day). The concept is similar to totaling daily rainfall measured in inches per day.
Total daily light requirements vary considerably between different plant species.
A good resource that provides DLI information on many crops is the Purdue Extension publication on daily light intervals — www.extension.purdue.edu/extmedia/ho/ho-238-w.pdf.
Seasonal monthly DLI has been published in maps prepared by Dr. James Faust at Clemson University, which are included in the above link. These are good for getting average light, but need to be adjusted down to compensated for the loss through the glazing and greenhouse structure.
Many environmental control computers include DLI in the weather data that they obtain. Light sensors both outside and inside the greenhouse at plant level will give accurate totals and can be used to adjust crop production schedules or crop timing.
The Spectrum Technologies, Inc. (www.spectmeters.com) Watchdog Model 2475 Plant Growth Station has the capability to record four environmental factors, including light. It requires a software package for your PC to integrate instantaneous readings into a DLI.
If the measured DLI is less than what is recommended, supplemental light could be supplied to make up the difference. This can be either high-intensity discharge (HID) sodium vapor or metal halide or one of the light-emitting diode (LED) lights developed for plant growth. An economic analysis should be done before purchasing supplemental lighting as it is marginal for most crops due to the high cost of electricity.
Light levels inside the greenhouse are reduced from 25 to 50 percent due to losses through the glazing and the shading from the structure. I have measures readings as low as 35 percent in a house that had old fiberglass glazing. Cleaning or replacing the glazing, moving some of the overhead obstructions (heat and water pipes, electrical conduit, poly ducting) can have a significant effect. Also, when building new greenhouses, locate the utilities along sidewalls or under the floor to reduce potential shade.
Bartok is a regular contributor to Greenhouse Management and an agricultural engineer and emeritus extension professor at the University of Connecticut. He is an author, consultant and a certified technical service provider doing greenhouse energy audits for USDA grant programs in New England.
Have a question? You can write John at firstname.lastname@example.org.