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Let me tell you a story. I was on a design consultation a few years ago, and there was a perfect spot for three dwarf Hinoki false cypress. Because my consultation customers can go anywhere to buy the plants I have recommended, I decided to use a story to illustrate the importance of buying just the right variety. I didn’t want them to end up at the box store where someone would put just any random evergreen into their hands.

“Be sure that you get the variety called ‘Nana,’” I told them. “There are many types of Hinoki that grow higher. In fact, I did a consultation for a local funeral home once and recommended that they use three ‘Nana’ Hinoki cypresses behind their sign. But they planted another variety and those have grown really tall and skinny. Now every time I pass by that place, I see the Father, the Son and the Holy Ghost looming over their sign.”

The customers laughed, but more importantly, they remembered. Two weeks later they were in our nursery with my plan, asking for the right variety of Hinoki. They couldn’t recall the shrub’s name off the top of their heads, so they handed the plant list to one of our staff members. As he was checking the plan, the husband told him, “We want to avoid growing the Father, the Son and the Holy Ghost!” The story had conveyed the importance of getting the right plant better than if I’d just encouraged them to do so.

You may have noticed that many who blog, speak, or write books about marketing emphasize the importance of storytelling. The fact is, stories function in several ways for any business. A story draws people’s attention. We perk up our ears or continue reading when a story is involved. Stories make information “sticky” so that it’s more memorable. My consultation customers weren’t going to remember “Hinoki false cypress,” but they did remember the punch line to my story. And finally, stories create human-to-human connections; such links sell plants and products without being a high-pressure sales pitch.

There are many ways to use storytelling to increase customer loyalty and your bottom line. Here are just a few suggestions:

If you’ve had personal experience with a plant, be sure to pass that on to your customers. A story that is a few sentences long that speaks to a plant’s hardiness or other desirable characteristics is akin to giving your plants a five-star review on online.

Use a story to begin blog posts or newsletters. These can be personal experiences or things your customers have told you over the years. After the story, sum up with the take-home message about the plant, product, or practice in question.

Every plant has a story. You can tell your own or use stories that are known in the trade. You might get a copy of “Of Naked Ladies and Forget-Me-Nots: The stories behind the common names of some of our favorite plants,” by Allan M. Armitage, and put it in your employee break room. When a customer is considering a plant and you’re nearby, if you know a short tale about that shrub, tree or perennial, tell them about it.

Hold a “Garden Story Night” or “Plant Story Slam” and invite people to share a story about a plant or their garden. Most such events have people sign up in advance and give each storyteller a time limit. Have attendees vote for the “people’s choice award” and award the winner a gift card.

Finally, your business has at least one story, and probably many more. Do your customers know how your operation came to be? Have you told the tale about the flood that washed your stock away? Have you written about the time the petting zoo goats you brought in for an event got loose and ate the perennials? Such tales create bonds between your company and the community.

Think about what you want your customers to know and remember, and then tell them a story about it.

The author is a speaker, writer and radio/podcast host who has worked at Hyannis Country Garden, an IGC on Cape Cod, for more than 20 years. She has her audiences convinced that C.L. stands for “Compost Lover.” Learn more at GardenLady.com.

Pesticides (insecticides, miticides, fungicides and bactericides) are still the primary means of managing arthropod (insect and mite) pests and diseases (fungi and bacteria) in greenhouse production systems because they are easy and convenient to apply, and generally very effective. Many facets of greenhouses favor pest and disease population growth, including environment (e.g. temperature, relative humidity and photoperiod), cultural practices (e.g., watering and fertility) and a continuous food source (lots of plants in the greenhouse that are spaced close together). Consequently, greenhouse producers apply pesticides to prevent or minimize plant damage. However, the continual reliance on pesticides promotes the development of pesticide resistance in insect/mite pest and disease populations.

This is the third article in a series of six scheduled for publication in 2019 and 2020 associated with pesticide resistance and resistance management of arthropod pests and diseases. In this article, we discuss the arthropod pests and plant pathogens that are more predisposed to develop resistance to pesticides.

Arthropod pests

Resistance develops at the population level and is an inherited trait with surviving individuals passing traits (genetically) to their offspring (young) or next generation, thus enriching the gene pool with resistant genes. Selection pressure for resistance increases as application frequency increases (number of times a pesticide is applied), and this is especially the case when pesticides with the same mode of action are applied in succession. Resistance can vary from one greenhouse to another based on pesticide use patterns. In addition, the prevalent movement of plant material globally can also impact resistance by exposing pest populations to pesticides with similar modes of action and transporting insects that have already acquired resistant traits.

In general, arthropod pests of greenhouse-grown horticultural crops are not predisposed to develop resistance, but the intense selection pressure placed upon pest populations as a consequence of the frequency of applying pesticides exacerbates the potential for the development of resistance. Most arthropod pests, including aphids, thrips, whiteflies and spider mites, have developed resistance to a wide range of pesticides in various chemical classes (organophosphates, carbamates, pyrethroids, macrocyclic lactones and spinosyns). In fact, more than 550 insect pest species have developed resistance to one or more insecticides over the past 50 years.

Many insect and mite pests encountered in greenhouse production systems have short developmental times and females have high reproductive rates, which can foster the likelihood of pest populations developing resistance. Below are the biological factors responsible for promoting resistance in insect and mite pest populations:

• short generation time
• multiple generations during the growing season
• high reproductive rate of females
• broad range of plants fed upon, which increases exposure to pesticide applications
• haplo-diploid breeding system. The male only has one set of chromosomes (haploid), so resistance genes are directly exposed to selection from pesticide applications. Consequently, this increases the potential for resistance developing

Insect and mite pests within greenhouse production systems can breed year-around, with many generations being produced and generations occurring simultaneously, which increases exposure to pesticides due to more frequent applications.

Furthermore, insect and mite pests within greenhouse production systems can breed year-around, with many generations being produced and generations occurring simultaneously, which increases exposure to pesticides due to more frequent applications. Pesticides are typically applied at short intervals, although this depends on the pesticide and residual activity (persistence), and a certain number of individuals may not be exposed to a pesticide application. These surviving individuals are likely to be resistant and will breed with other surviving resistant individuals resulting in the production of a population of highly resistant individuals — consequently, a pesticide-resistant population has been selected.

Another problem is that localized or isolated insect or mite pest populations may develop resistance faster than mobile arthropod pests. The reason is that the intense selection pressure associated with the frequency of applying pesticides reduces the number of susceptible individuals that can breed with resistant individuals. This is especially true in most greenhouse situations where there is not a continuous influx of susceptible individuals entering greenhouses from outside throughout the growing season.

Plant pathogens

Plant pathogens, like fungi and bacteria, can become resistant to fungicides and bactericides. They differ in some ways from insects and mites in that they cannot move on their own. That means that when a population becomes resistant to a fungicide, the population will not spread from a single crop within a greenhouse or between greenhouses, or especially from state-to-state. However, we make up for that lack of mobility by obtaining propagative materials from many sources worldwide and then selling our plants all over the world. This means of spread of resistant populations is the main way we create a resistance incident in one operation a worldwide problem in short order. We are a very effective vector in our own right.

The pathogens that are most likely to become resistant have certain characteristics like short reproduction times (for bacteria it can be 20 minutes). Thus, many generations are created quickly, making the chance of a genetic change higher, leading to the development of resistance. Another characteristic of fungi that makes resistance to fungicides possible, is the production of many, many, many spores. One good example is Botrytis blight. Resistance in some populations of Botrytis to SDHI fungicides (Fungicide Resistance Action Committee (FRAC) 7 — like those containing boscalid) have been reported on many crops including fruit trees, strawberries and most recently cut flowers. Other plant pathogens that can develop resistance very quickly include the downy and powdery mildews because they also produce lots of spores.

Previous page © Greenhouse Management; Photo Illustration © arlindo71 | iStockphoto

Sometimes resistance develops because there are very few effective products that can be used for a specific disease and the products represent only a few FRAC groups. The bacterial pathogens are primarily controlled with copper-based products (FRAC M01) and historically antibiotics like streptomycin. When a crop is sprayed with copper or an antibiotic consistently and without alternation, resistance in the bacterial population can develop very quickly — sometimes in one season. This has been shown in Florida on a number of ornamental crops starting in the 1960s. Luckily, we have more choices today and can alternate copper with some of the biopesticides that contain Bacillus and certain plant extracts. These compounds are very effective and are often equal to copper bactericides, and also make excellent rotational partners.

At other times, the product works well and is relatively inexpensive, leading to its overuse. I believe this is what has happened with the FRAC 4 product containing mefenoxam (originally metalaxyl) and Pythium resistance. So many greenhouse producers relied exclusively on this active ingredient that resistance developed over 25 years ago. However, mefenoxam is still a viable choice for Pythium control when proper rotations are employed using multiple FRAC groups including FRAC 14 (etridiazole), FRAC 21 (cyazofamid) and FRAC 11 (strobilurins like fenamidone).

The nature of the products we employ currently for fungi makes resistance development more likely than when we primarily used broad-spectrum fungicides (sometimes referred to as a “shotgun approach”). For instance, products containing the active ingredients: chlorothalonil and mancozeb had multiple means of controlling the fungus by interfering with many different systems in the plant pathogen. It is still rare to see resistance to these active ingredients even though they have been used for more than 40 years. The narrow targeted products of today, like the strobilurins, sterol inhibitors (FRAC 3) and SDHI fungicides are predisposed to have fungi develop resistance since fewer changes or alterations in the fungal genetics are required. These products are better for the environment due to limited non-target effects but are also more susceptible to the development of resistance by plant pathogens.

Raymond A. Cloyd is professor and extension specialist in horticultural entomology/plant protection at Kansas State University. You can reach him at rcloyd@ksu.edu. A. R. Chase is president of Chase Agricultural Consulting. You can reach her at archase@chaseresearch.net.

‘Tis the season! Another year of poinsettias has arrived and with it, thoughts of how to recoup more revenue on this crop that has been commoditized. One poinsettia crop that is not widely grown is the standard, single or straight-up form. These names are all synonymous for the same product — one utilizing multiple, unpinched cuttings instead of fewer or a single pinched cutting(s). While poinsettias finished from pinched cuttings are now the most common and widely grown form, poinsettias were originally grown using this multiple unpinched style.

There are several reasons why these unpinched plants are popular among both producers and consumers. First and foremost, the finished plant quality is different from pinched varieties in a few different ways. The final bract size for the unpinched plants are generally larger than those from pinched plants, and blooms also have more cyathia. If side branches are allowed to develop on unpinched cuttings, this can also result in a fuller plant, though these are removed by some producers. For these reasons, the straight-up poinsettias are often referred to as “florist quality,” for premium appearance.

In addition to plant appearance, there are also advantages aside from finished plant quality. For producers, straight-up plants have a short production time compared to the pinched forms, since the time under non-inductive long days is shorter. For example, a 6-inch container of three or four unpinched cuttings requires two to three weeks less than pinched than other varieties. The exact amount of time saved varies with container size, geographic location and cultivar vigor. However, all things equal, an unpinched poinsettia will require less bench time than the same size container finished with pinching.

For pinched poinsettias, working among the crop and handling them can result in unwanted stem breakage. When branches break off pinched plants, it not only creates a wound that can serve as an entry point for diseases and diminish plant vigor — losing branches can also render plants unsaleable. If lower branches break, plants may still be saleable, but sometimes the gaps created in canopies are too unappealing and plants are then unmarketable. With unpinched poinsettia forms, reducing breakage means less shrink and loss.

The cost for propagative material — whether unrooted or rooted cuttings — increases for unpinched poinsettias compared to the pinched form. For 6- to 6.5-inch, 7- to 7.5-inch, 8- to 8.5-inch and 10-inch containers, you will use 3-4, 4-5, 5-7, or 7-10 cuttings per container, respectively. While this does increase production costs, it doesn’t make these plants less profitable; in fact, these unpinched plants can improve your bottom line.

While the factors affecting profitability will vary with each firm, unpinched poinsettias can be a more profitable crop than pinched based on several reasons. As mentioned earlier, unpinched plants have a shorter production time, requiring less bench space. Additionally, the shorter production time will save labor, as will not having to pinch and remove leaves. When planting unpinched containers, selecting similar-sized cuttings can also simplify and reduce plant growth regulator applications, further reducing input costs. The reduced shrinkage from plants lost to stem breakage also help the bottom line. Finally, the high quality of unpinched plants with large, showy bracts can command a higher price at the wholesale and retail levels.

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Tissue culture is a primary propagation engine for new infusions of disease-free germplasm. Though commonplace for many species, a frequent challenge for tissue culture plants remains achieving high post-acclimatization (or hardening) survival and vigorous growth. While each tissue culture method used (micropropagation, organogenesis, embryogenesis or embryo rescue) has its quirks, the need is the same once removed from jar or tub and transplanted: Keep them alive and get the root and shoot growing rapidly.

The plant’s in vitro existence in the lab is physiologically a fat and lazy one if protocols are reasonably optimized. A tissue culture vessel is a closed, protective cocoon. It creates a near-saturated humidified environment (>95% RH), without air movement, and where light levels are generally moderate and controlled. Lastly, nutrients and water are freely provided for plant uptake via a semi-solid medium.

The ex vitro hardening process requires plants to adjust to much wider and more rapid swings in environmental conditions. This must be carefully managed by greenhouse and nursery growers in a stepwise manner. While vigorous species can manage this process with seeming ease, other species and sometimes specific cultivars can be much more challenged and require slower and/or longer periods of adjustment.

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Plant quality

The natural tendency when problems arise is to focus on the acclimatization environment. Is it too dry, too wet, too bright, too warm or too cold? Most often the plant quality coming from the lab largely determines the outcome well before the plants are ever exposed to the external environment.

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Quality at the lab

Development of cultural methods for a new cultivar or species from tissue culture often poses the eternal “chicken or egg” question. When early greenhouse outcomes are poor, “is it the greenhouse or the lab’s fault”?

The best method of resolution from the seemingly circular discussion is for the lab and greenhouse to collaborate. A useful first question can be, “What is the range in morphology that is currently coming to the greenhouse/acclimatization space?” If it is highly variable or not tracked, this suggests an opportunity for all involved to learn and to test. This can be done by planting plants with similar morphology and observing the result under current acclimatization conditions. If a morphotype is failing at a high frequency, and for obvious reasons (lack of general size, lack of foliage, lack of roots, hyperhydricity, contamination), then lab protocols need to improve and/or transplant specifications need to be made more stringent. Often the short-term answer (albeit painful) is to not ship or transplant low-quality material. While this is obvious for plant survival, it can also substantively impact final deliverable yield due to insufficient growth. This downstream loss can be very significant and costly. Understanding the full downstream cost implications of poor tissue culture stock often justify significant investments in process and infrastructure in the lab and acclimatization stages.

“Green plant with roots” is not a specification unless most everything transplanted survives and grows well.

Transplant selection at the greenhouse

“Green plant with roots” is not a specification unless most everything transplanted survives and grows well. In most cases, additional objective criteria are required: root length, stem length, leaf number, longest leaf length, etc. Note that there are at least two aspects of “the shoot”: the stem and the foliage. Length and caliper of the stem is critical during transplant, and is the conduit for water, sugar and nutrition transport. The foliage likewise can be broken down into the number of leaves, leaf size and net foliar surface area. The sum of plant foliar surface area largely determines the growth rate potential in well-rooted situations. Leaf and shoot characteristics tend to be broadly correlated, but not always, and particularly coming from artificial environments.

While the presence of a root is generally positive, there are some important caveats. Allowing roots to extend much past soil matrix depth can result in decline on the root-to-shoot ratio that can cause physiological stress if root trimming is severe.

Secondly, longer roots that are more vascularized (brittle) at their base are more prone to damage and challenging to transplant. For these reasons, planning for expected rooting duration in the lab schedule is very important, but should also not be set in stone. The lab should always visually verify a batch has attained transplant specifications before it is transferred to acclimatization. Finally, timely inspection and real-time feedback by greenhouse staff provides a final opportunity to catch issues for correction in the next production batch.

The ex vitro hardening process must be carefully managed by growers in a stepwise manner.

Despite best efforts, sometimes long roots just cannot be avoided. Root growth in some species or cultivars are just strongly favored over shoots in vitro. In this case other factors such as transplant media volume, soil media components and transplant method may need to be altered. This will be further discussed in the next installment of the series.

A plant is ultimately the sum of its parts, and because of this transplant decisions are made on plants, not individual plant parts. Use of large photo examples is a critical quality control tool for aiding transplanter decision-making. Photographs should have a sense of scale and display “ideal,” “minimally acceptable” and “clearly unacceptable” plants. Several examples of each category should be present. During routine discussion with staff, these pictures can be a very useful tool to help guide discussions and provide a common frame of reference and institutional memory of standards.

Frequent and well-communicated training and quality control feedback along the transplant line cannot be overemphasized. While it is obvious to provide feedback to new workers, experienced staff and management also benefit. Drift in acceptable quality can occur very slowly as lots from the lab can evolve over weeks and months without anyone taking notice until plant outcomes begin to mysteriously change. Discussion about quality supports both workers and management balance the competing goals of achieving high transplant rate versus maintaining transplant quality. In the final analysis, the combination of clear specifications, training and feedback will greatly improve the odds of greenhouse benches being filled with uniform, high-vigor trays that come from tissue culture origin.

The author is a technical sales advisor for Quick Plug.