Photo: Istock.com

Syngenta is committed to working with nursery and greenhouse growers to develop comprehensive solutions to the pest and disease issues they face. These solutions put their innovative products into agronomic and rotational programs that consider modes of action, application methods, preferred timing and application rates.

Agronomic programs offer growers comprehensive, long-lasting management of insects and diseases affecting a specific crop. With a focus on proactive rather than reactive treatments, these programs can help growers save resources by avoiding curative applications.

“Agronomic programs provide a framework for the grower to follow that addresses the primary problems they are likely to encounter when growing a particular crop,” says Nancy Rechcigl, Technical Field Manager, Ornamentals at Syngenta. “It helps to ensure their success by reducing or preventing the problems that would affect the quality and sell-through of the crop.” Having an agronomic program does not eliminate the need for scouting. Monitoring the crop and environmental conditions are still important for proper timing and application of treatments.

A key component of an agronomic program is a well-researched rotation, which serves as a valuable resistance management strategy.

“We take into account the primary insect and disease problems the crop may develop over the course of production. Then we select two to three products with different modes of action that have strong performance and residual activity for each problem. Each product is put in a rotation at a point where it will provide the best benefit,” Rechcigl says. “So the agronomic program is robust and built with a strong resistance management strategy.”

Syngenta introduced many downloadable agronomic programs in early 2017. Through the online resource, GreenCastOnline.com/Solutions, growers can search for and download programs fit for their operation.

A downy mildew program

Incorporating products with systemic activity and different modes of action reduces the risk of resistance and is key to successfully controlling downy mildew, a potentially devastating disease. A program using Segovis^®, Micora^® and Subdue Maxx^® fungicides delivers long-lasting protection with differing modes of action so that impatiens and other susceptible annuals and perennials can thrive in the garden and remain viable crops in growers’ operations.

In 2016, Fulya Baysal-Gurel, Assistant Professor at Tennessee State University’s Otis Floyd Nursery Research Center in McMinnville, Tenn., conducted a study to evaluate fungicide rotations at 7- or 14-day spray application intervals for the control of downy mildew on roses.

“Rose plants can be latently infected with the downy mildew pathogen,” Baysal-Gurel explains. “When the conducive conditions such as cool weather and high humidity occur for disease development, symptoms may appear overnight. Therefore, preventive fungicide applications in a rotation are critical to control downy mildew.”

The initial fungicide application was Subdue Maxx (2 fl oz/100 gal) and Micora (4 fl oz/100 gal), which was made after observing the first symptoms of downy mildew on Pink Double Knock Out^® roses. Next, Mural^® fungicide (7 oz/100 gal) and Segovis (2 fl oz/100 gal) were alternated at 7- or 14-day application intervals.

“Fungicide rotation programs at 7- or 14-day application intervals equally and significantly reduced downy mildew incidence as well as the average number of infected leaves compared to the non-treated control,” says Baysal-Gurel. “This study also showed that the 7-day rotation program significantly increased plant height and width compared to the non-treated control plants.”

The strong residual performance and broad-spectrum activity of Mural allows it to be used in a flexible manner depending upon where its strength is needed, Rechcigl says.

“Placing Mural in the rotation with strong, systemic oomycete products, like Segovis and Subdue Maxx, provides comprehensive control of most diseases a grower may encounter on roses,” Rechcigl adds. “Mural provides strong activity on leaf spot diseases, powdery mildew and rusts, and it also has activity on downy mildew diseases.”

Mural also has the benefit of having both translaminar and systemic activity. It can be used as a spray or a drench —depending on the grower’s primary targets or problems.

“Growers may use it as a drench to control root and stem rots such as Rhizoctonia and get the systemic benefit of suppressing powdery mildew on the crop as well,” Rechcigl says.

Drench applications

Baysal-Gurel and her team conducted another study to evaluate systemic fungicide drench applications for the control of downy mildew on roses. Treatments were Segovis (1.0 fl oz/100 gal and 3.0 fl oz/100 gal), Subdue Maxx (2 fl oz/100 gal) and two Syngenta experimental products A13836B (2.75 fl oz/100 gal) and A14658C (20 fl oz/100 gal). Treatments were applied as a drench at the first signs of downy mildew with a volume of 20 fl oz per No. 3 nursery container.

According to Baysal-Gurel, all fungicide treatments “significantly reduced the final severity rating, disease progression, downy mildew incidence, and average number of infected leaves compared to the non-treated control. The severity of downy mildew and disease progression among fungicide-treated plants was significantly lower in plants treated with the higher rate of Segovis.”

She also notes that “all treatments significantly increased the plant height and width compared to the non-treated control. Our drench trial shows the benefit of using systemic products in the treatment program — with one application providing excellent protection for 30 days.”

Segovis is effective in this rotation because of its translaminar and systemic activity, which will likely extend the grower’s treatment interval while maintaining good protection, says Baysal-Gurel.

Syngenta has tested this rotation and many more to ensure their effectiveness in the greenhouse or nursery. By developing these programs, Syngenta can help save growers’ time and resources so they don’t have to spend their time looking for the appropriate product to use and ensuring it controls the insect/disease and is compatible in their operation.

“The programs provide efficiency and economic benefits to the grower. It will help them save time since a comprehensive program is already developed and ready to be implemented, and it has a built-in resistance management strategy as part of the program, which is critically important,” Rechcigl explains. “Being prepared also means growers are less likely to encounter the problems they’re trying to prevent with fewer applications, so quality remains high and shrink and input costs remains low. Curative or corrective treatments often require higher rates and more applications, therefore increasing production costs.”

These agronomic programs have been tested so growers can be confident using them to grow beautifully strong plants that flourish long after they leave the production facility.

©2017 Syngenta. Important: Always read and follow label instructions. Some products may not be registered for sale or use in all states or counties and/or may have state-specific use requirements. Please check with your local extension service to ensure registration status and proper use. GreenCast^®, Micora^®, Mural^®, Segovis^®, Subdue Maxx^® and the Syngenta logo are trademarks of a Syngenta Group Company. Photos are either the property of Syngenta or used under agreement.

Horticulture runs in the family for sisters Christa (Walters) Steenwyk and Karin Walters, whose grandparents opened Walters Gardens in 1946. Their father, John Walters, still serves as CEO of the wholesale perennial growing operation based in Zeedale, Michigan. But Christa, 35, and Karin, 31, are already shaping how Walters Gardens will look under third-generation leadership. Inspired by their grandfather’s appetite for risk, the sisters are stepping outside of their respective roles as creative director and marketing director to push the company — and the industry — forward.

GM: How did you end up in the family business?

Karin: We’ve both technically worked here since we were 14 — weeding, cleaning offices, collecting seeds off baptisia, digging out daylilies in the field. We’d done a little bit in every department before working full-time in marketing.

Christa: I think part of my dad’s strategy was to instill work ethic by having us do jobs that weren’t so fun or pretty, to encourage us to go to college and find careers for ourselves. I went to school for graphic design in Chicago. After a while, I decided to move back to Michigan, and my dad said, ‘Try working here between jobs.’

Then I found the fun side of horticulture. You’re working with one of the best products: plants. Another big draw is how friendly people are. I was hooked, but it wasn’t something I thought I’d pursue when I was younger.

Karin: I had no plans of going into the family business when I went to college, either. I majored in English, and when I had to start looking for jobs, I wasn’t sure where to begin. There was a position open in the marketing department so my dad said, ‘What do you think about working for me?’

GM: Why is this business important and exciting to you?

Christa: My dad will be at Walters Gardens for a long time, but as he starts to transition, it’s important for us to carry on the tradition and keep an enjoyable work environment. We respect the generations above us, and want to continue that legacy.

[To grow the Walters Gardens family], we have to help people who are new to the industry feel included — mentor them, encourage them, help them figure out what they want to do in their career. It’s top-of-mind for us to keep young people passionate about gardening.

GM: What are the biggest challenges facing the industry, and how are you overcoming them?

Karin: The industry isn’t really expanding; it’s staying the same. Maybe there’s a little growth, but if you have a success story, it’s probably because a competitor went out of business. You have to be creative and aggressive [to grow in this industry].

Christa: Our grandpa offered us some advice about the struggles he went through during his career: Stay ahead of the game. He’s always taken risks; he was one of the first to establish a tissue culture lab — which we now use to initiate plants that come out of our hybridizing program.

Karin: He was also one of the first to introduce a patented plant. When we interviewed him for our 70th anniversary, he said a lot of people told him he was crazy for his choices — having certain plants or buying a farm he couldn’t afford.

Christa: He jokes that some chances he took didn’t work out, but a lot of them did. So our challenge is [deciding] what to take chances on, because we always want to be doing something new. If we didn’t make some changes during the recent economic downturn, if our company just stayed how it had been 10 years ago, would we be here today?

GM: Why aren’t more young people excited about this industry?

Karin: Honestly, I don’t think it occurs to people that there is a horticulture industry. If you’re in FFA or 4-H, you’re thinking about agriculture, so usually we get overlooked by ag. They don’t understand the opportunities here.

Christa: There are so many types of jobs in this industry, but people don’t see all those jobs when they think ‘greenhouse.’ We should do a better job of offering internships to show students what all this industry has to offer.

A lot of people who are interested in growing want to start with vegetables. I love industry professionals like Brie Arthur, who grow vegetables but also talk about the importance of growing perennials, shrubs and annuals with those vegetables.

A lot of companies outside this industry are talking about connecting with influencers, like bloggers that talk about fashion or food. How can the horticulture industry partner with people like that? Gardening is a lifestyle, and those partnerships could help us engage with customers.

GM: How could the industry be more supportive of young professionals?

Christa: New horticulturists — whether they’re young or just new to the industry — they’re looking for opportunity. They don’t want to be stuck in a job. They want flexibility to work from home or take an afternoon off and make it up later. They want opportunities to travel, to attend trade shows, to go to seminars.

Karin: If you’re in a position to send a young person to an industry event like Cultivate, but you’re sending the same people every year, take a chance on someone who’s never been before.

Christa: And if you go every year and they’re not giving someone else a chance, offer to stay back. Someone did that for me and it meant the world to me.

GM: Speaking of traveling to tradeshows, describe your trip overseas earlier this year.

Christa: One of my friends, Bob Blew from Centerton Nursery [in Bridgeton, New Jersey], and I have been talking for years about how to bring together industry professionals our age. We both like to travel, and we run into each other at events. We ended up traveling to IPM Essen [in Germany] with about 10 next-generation business owners and other industry professionals our age, which gave us great perspective. We went on two days of tours to various nurseries, and there was something for everybody — a wholesale nursery, a finished grower, a retailer.

This was our first trip with this group; we wanted to keep it as unorganized yet organized as possible. Anyone who wants to travel with us is welcome. We’re hoping to do IPM every other year, and a couple of us are going to the Perennial Plant Association (PPA) Symposium this year.

Karin: We each get excited about different things, so it’s really interesting to hear what people got out of the trip. Plus, once you become friends, you can ask them questions about the industry, like, ‘Are you noticing this trend in your business?’ You’re more interconnected.

GM: Does the industry need an association for young professionals, or are small grassroots groups more effective?

Christa: We’ve talked about that in depth, and I don’t think we came up with an answer. Some people can be turned off by something too organized, and they like more easygoing get-togethers. But it would be cool to have a group that would have speakers and panels and idea groups.

Karin: This generation is eager to make some changes, but [their perception] is that associations don't get anything done.

Christa: They need to start fresh to make [the loosely organized group that] we’re looking for. But in addition, existing conferences like PPA should have a night or part of the event where young people have a chance to get together. And I notice a lot of [association] boards are always industry vets. Get some perspective from the younger generation, because both perspectives are important.

GM: What can the industry do to remain more relevant to young consumers?

Christa: You’ve got to keep your mind open and try as many things as you can to reach that consumer. Encourage people who aren’t necessarily into gardening to come to events by doing butterfly exhibits or having bands play. We’re continuously thinking about people that are into decorating their homes or cooking local food, and how to encourage them to get into gardening. How can we reach them with what they’re already doing? Don’t just focus on gardeners; expand beyond that.

Karin: I don’t think we need to totally revolutionize the horticulture business, but we need to find a way to appeal to those people. [Look beyond] our industry, to general trends like same-day delivery on Amazon — is that feasible for us? For example, when I want to find specialty plants, I first look online. That’s the mindset [of our generation].

Christa: Even though Target is five minutes down the road, I’d rather go to Target.com and order in-store pickup so I’m not spending as much time at the store. Could more local garden centers put their inventory on Google Shopping results, and offer in-store pick-up?

Karin: It’s good to keep tabs on those trends, whether we can do it or not, because we’re kind of an old-school industry. Our natural inclination is to stick our head in the sand and ignore what’s going on, and that’s a mistake. But I also think it’s a mistake to jump on every single trend.

Christa: We have to continuously educate ourselves on what the home gardener is doing to stay relevant.

Brooke is a freelance writer based in Cleveland, Ohio, and a regular contributor to Greenhouse Management and its sister publications.

Editor’s note: This article originally appeared as two breaking news stories and a feature on Greenhouse Management magazine’s website May 14, May 17 and June 2.

Following the news that orange-colored petunia varieties in Europe had been found to be genetically engineered (GE), the United States Department of Agriculture (USDA) launched an investigation into other potentially affected varieties imported, distributed and grown in the U.S. without appropriate authorization.

Petunia breeders have been in contact with the USDA, which circulated a document dated May 11, 2017, listing some of the potentially affected implicated varieties and instructions for how to destroy the seed and plants.

According to the document, “USDA is currently conducting genetic tests on implicated varieties for which we have obtained samples. These tests will confirm whether these petunias are genetically engineered. As we obtain results from the genetic tests, we will provide updated lists of confirmed GE petunia varieties.”

The most recent update before this magazine went to press was on June 20:

• African Sunset
• Amore Mio
• BigDeal Freaky Fuchsia
• BigDeal Salmon Shimmer
• Capella Red
• Cascadias Simply Red
• ColorBlitz Bright Red, also known as Glow Bright Red and Viva Bright Red
• ColorBlitz Fire, also known as Glow Fire and Viva Fire
• ColorBlitz Pink Morn, also known as Glow Pink Morn and Viva Pink Morn
• Confetti Garden Twist
• Crazytunia Cherry Cheesecake
• Crazytunia Citrus Twist
• Crazytunia Fire Cracker, also known as KaBloom!
• Crazytunia Maniac Pink 
• Crazytunia Sparky Improved
• Crazytunia Star Jubilee
• Crazytunia Swiss Dancer
• Fortunia Early Orange
• Hells Bells Improved
• Hells Bells Orange
• Hells Fruit Punch
• Hells Glow
• Littletunia Red Fire
• Perfectunia Cherry Pop
• Perfectunia Coral Blast
• Peppy Cerise
• Peppy Red 2017
• Potunia Dark Red
• Potunia Plus Neon 2017
• Potunia Plus Papaya
• Potunia Plus Red

To view USDA's full updated list, visit bit.ly/2sSY1Ek

It all started when Evira, the Finnish Food Safety Authority, released a statement on April 27, 2017, regarding the discovery of genetically engineered orange petunias. The color of one particular petunia — American Takii's African Sunset — captured their attention, and since then, more orange petunias and those in colors other than orange have been added to the list of plants that possibly contain genetically engineered plant material.

“On May 2, 2017, APHIS [Animal and Plant Health Inspection Service] was informed by Selecta Klemm GmbH & Co. that one of its petunia varieties — an orange petunia — was potentially genetically engineered and had been imported and moved interstate without required authorization by APHIS,” according to the May 16 statement from the USDA. “This led to testing by USDA of numerous petunia varieties, which confirmed this particular variety and several others are indeed GE and meet our regulatory definition of a regulated article under APHIS regulations.”

A USDA spokesperson said because GE petunias do not pose a risk to humans or the environment, the government agency is not asking consumers or retailers to destroy the petunias. They have asked breeders, growers and retailers to “voluntarily withdraw GE plants from distribution” and sent instructions for proper destruction to breeders, growers and distributors. The plants have been in the market for years, and it’s a compliance issue, not a safety concern, the spokesman said.

“We are asking that the GE petunias be destroyed at the earliest opportunity, and importers and distributors have been working as quickly as possible to accomplish this,” a USDA spokesperson said by email when asked if there was a specific deadline for destroying the plants.

Breeder response

The implicated plants were not properly registered with the USDA as GE plants because no one seemed to know that they contained or were bred with GE plant material.

“We were surprised by the finding of genetically modified petunias, stemming from research in Europe,” says Bethany Shively, director of communications for the American Seed Trade Association. “… We have been working closely with USDA APHIS-BRS to facilitate industry coordination and accurate information-sharing. Seed and plant companies are also conducting their own independent tests, and pulling varieties in question off the market.”

Chris Berg of Westhoff echoed the sentiment that the industry was taken aback by this news.

“It is something our industry has never dealt with before and came as a complete shock to the breeder community, but I’m happy to see how everyone has been working together to find a common solution that will be helpful to us all,” Berg says.

Since the news broke at the end of April in Europe, petunia breeders have conducted their own tests to determine which plants are affected after it was discovered it was not just orange petunias that may have been bred with a genetically engineered plant.

“We were completely shocked by the findings,” says Mike Huggett, national sales manager for American Takii. “We sent out the recall through our broker network and instructed the growers to stop sales [on African Sunset], and following that, we conducted some other trials internally and confirmed Trilogy Red and Deep Purple had foreign DNA in them, so we initiated a recall on those as well.”

American Takii only breeds using conventional means, Huggett says.

“Takii’s reaction was just to reclaim as much as we could because as far as the company is concerned, we don’t do any genetically modified plant material, we don’t practice in it, we don’t want to,” he says. “I’m not as much worried about the flowers as I am the perception about the vegetables. That’s when consumers get worried. The petunia loss hurts, but in the bigger scheme of things, I think it’s the perception of what the company is doing. You don’t want to be associated with a GMO.”

The silver linings for American Takii are that the GE plant is not harmful to consumers, and its recently released Evening Scentsation petunia tested negative for the GE material, says Steve Wiley, COO and general manager.

“It’s an ever-expanding list,” Wiley said of the GE petunias implicated by the USDA. “It’s one of those things where I think [the genetically engineered plant] sprang up during an age of innocence and perpetuated itself because no one even knew to look for it or fathomed that it was in the germplasm chain.”

Huggett credits the USDA and the American Seed Trade Association for their “quick work in helping us navigate through this.”

“You can’t plan for this because it wasn’t our intention,” Huggett says. “We have to start picking up the pieces.”

Genetic testing underway

When asked if the foreign genetic material stems from a documented 1980s experiment at the Max Planck Institute for Plant Breeding Research, a USDA spokesperson responded: “We’re aware of a gene engineered into petunia from corn in the 1980s. We don’t know if this is the genetic material in these particular GE petunias. Genetic testing is underway.”

Breeders are conducting their own tests, and Berg of Westhoff says they are not limiting their tests to petunias.

“We have to first start by testing everything. All plants in our current assortment as well as all the plants in our breeding house. The Finnish test was looking specifically at orange lines of petunias, but we can’t say for absolute certainty that this gene hasn’t been incorporated into our other varieties,” Berg says. “And since we have no idea when and how it entered our gene pool, we need to screen all of our plants we’re breeding with.”

Westhoff is concerned about how this will impact plant supplies next year.

“Because GE plants are regulated by the USDA, we expect there will be several varieties from many breeders that won’t be available on the market next year,” Berg says. “But the USDA has been very cooperative so far, and I feel they’ll help our industry get these plants back in the hands of consumers in the long term.”

Each section of the supply chain has been affected differently by the discovery of GE petunias, says Craig Regelbrugge, AmericanHort senior vice president.

“It’s obvious that there’s been some impact throughout the supply chain, and particularly in the breeder-distributor-grower realm,” Regelbrugge says. “The situation unfolded late enough in the season that it mitigated the impact significantly, compared to what it could have been. But certainly, there has been negative impact, and everybody is working through the short-term response. The conversations will soon turn more in earnest to the medium- and longer-term considerations.”

Commercial companies or a consortium of companies will need to decide how to move forward; some might cover losses to other companies further down the supply chain, Regelbrugge says.

“This has been a very, very unique situation in that there’s not any evidence that anybody knowingly engaged in distributing an unauthorized genetically engineered variety or varieties,” he says. “So, it’s been a good faith effort to respond proactively. And obviously there’s been some product that would have moved through the supply chain to be sold and hasn’t been, so there’s loss associated with that.”

Retail impact

As inventory shrinks, it makes economic sense to consider raising the price of petunias, says Dr. Bridget K. Behe, professor of horticultural marketing at Michigan State University.

“If there’s only a limited supply, that’s the best way to help the flow of supply and demand, to increase the price, because only the people who see the value in that, who have to have their petunias, are going to be willing to pay that premium price,” Behe says. The registration process required in order for breeders to produce and distribute the affected petunia varieties could take several years.

Behe notes that she is not advocating doubling or tripling prices, but says it is a good option for retailers to increase the margin on a product that will likely be in short supply. “If you could sell it and make 10, 20, 50 cents more per item, why wouldn’t you?” she asks.

Despite rumors, there is a small chance that breeders would request to fast-track the approval process for GE petunias because they would likely not have enough information to do so, a USDA spokesperson says.

Moving forward, the industry will have to monitor consumer acceptance of GE petunias, Regelbrugge says.

“Not everybody is accepting, but there are plenty of genetically modified items in the food system these days,” he says. “So, the pragmatists might say, ‘Yeah, using a corn gene to create a different flower color — if people like the flower color, what’s the harm?’ But I don’t know that that decision has been made by anyone yet.”

As has been the case with opponents of neonicotinoids, a vocal segment of people could cause a backlash, and they could affect change, Behe says. But because petunias are not edible, she doesn’t think many consumers will push back.

To prevent this from happening in the future, Wiley of American Takii says the company will examine their testing procedures when bringing in new germplasm and test all of their other commercial lines. But he sees opportunity in the chaos.

“There may be some [genetically engineered] red or blue varieties that will be pulled from the market, and we may have other colored varieties we can substitute,” he says. “The pot is going to be stirred based on the gap that this creates.”

This is a developing story that we will continue to report on as more information becomes available. Michelle Simakis is editor and Conner Howard is assistant editor of sister publication Garden Center magazine.

Appearing from seemingly out of nowhere, broad mites descended this year upon Casa Verde Growers in Columbia Station, Ohio, resulting in what section grower Jen Kolenc calls “broad mite apocalypse 2017.”

“By and large, I don’t see mites in here, and I certainly haven’t seen broad mites to this extent in my entire tenure,” she says. “I spent four springs here at Casa Verde, and then I did three years over at Heartland Growers in Indiana. I never saw broad mites like this.” Usually, Kolenc doesn’t spray miticides, but that has changed this year.

Broad mites and other tarsonemid mites, such as cyclamen mites, wreak havoc on growers all over, as do spider mites. However, their attributes and the problems they present differ.

Tarsonemids are microscopic — less than one-one hundredth of a millimeter — and require a microscope to be seen, says Dr. Raymond Cloyd, professor and extension specialist in horticultural entomology and plant protection at Kansas State University. Two-spotted spider mites, within the tetranychid family, are roughly two to four millimeters in size and can be seen with the naked eye.

The two mite types often feed on the same crops — such as gerbera daisies — but they feed on different parts of plants, Cloyd says. “The spider mites are feeding on the leaves because they need the chlorophyll,” he says. “Broad mites feed on the terminal growth of the leaves.”

Despite their differences, prevention and control of the two mite families are comparable. Because mites can't fly, growers will not be able to catch them on yellow sticky cards, so they should monitor their plants individually, Cloyd says. “The control is always going to be good sanitation and throwing away plants that are heavily infested,” he says. “That’s probably the best thing. But it takes also preventative action — scouting, looking for damage — and if you see it, determining if it’s broad mite. If it is, you may have to spray with a miticide — and the same for spider mites — there are a number of miticides that you can spray for both.”

One of those miticides is Akari, a contact miticide from SePRO, which contains the active ingredient fenpyroximate. In addition to controlling tarsonemids and tetranychids, Akari also controls eriophyid mites, and suppresses mealybugs and whiteflies.

Several years ago, Cloyd tested Akari on tetranychids, and he was pleased. “We did get some positive results with high mortality of two-spotted spider mites,” Cloyd says.

Spider mites

This year, Julian Figueroa, facility manager and grower at one of Riverview Flower Farm’s three locations in Seffner, Fla., has sprayed Akari to successfully control spider mites. “So far, we don’t see any insect population growing after the spray,” Figueroa says. “We were trying to control some whiteflies and a few mites that we have in some areas, and after the spray, we didn’t see anything.”

Figueroa has worked at Riverview, which has about 12 acres of undercover space, for one year, but he has worked in other greenhouses and says mites are consistently an issue. At Riverview, the mites appear mainly on pentas and lantana, but also on others, such as Cuban Gold.

In a mist blower with a three-gallon capacity, Figueroa says he uses three ounces of Akari, and sprays it over about one acre of production space. He uses Akari in a rotation with chemicals from different IRAC groups. So far this year, he has sprayed the miticide in the first week of February and the first week of June.

Almost every day, the growers at Riverview’s Seffner location scout for insect damage on the greenhouse’s crops, Figueroa says. “They know the insects and everything, so if they see something that I don’t see, they just tell me right away and we figure out right away how we’re going to treat it,” he says.

Broad mites

At Casa Verde Growers, which has about 24 acres under plastic and glass, employees walk through the greenhouse two or three times a day to look for insects, Kolenc says. She recalls stumbling across spider mites spinning webs on eggplants. “I’m like, ‘Oh, you jerks! You jerks!’ Kolenc says. “I was like, ‘All right, go get the miticides.’”

Despite run-ins with spider mites, much of Kolenc’s pest control in 2017 has been focused on broad mites. She sprays Akari in a rotation with four other miticides from different IRAC groups. “Usually, earlier in the spring, I’m spraying for sucking insects about once a week, and then when we get into this time of year when things are little bit more serious, the pest population is a little higher, I’ll go two times a week,” she says. “Now it’s just adding miticide.”

Graphic information courtesy of Raymond Cloyd

Casa Verde Growers’ propagation department frequently tank-mixes many miticides, insecticides and fungicides and sprays their plugs and cuttings, so everything is pretty clean by the time it comes to the finished grower side of the business, Kolenc says.

“I would say with the Akari and with the rotation, we’re starting to see them knock back now,” Kolenc says. The dahlias seem to be the main target. “Between when we saw damage, cut them back, sprayed them — I would say it probably took three to four weeks before we saw a complete recovery where we went from absolutely not saleable to mostly salable,” she says.

—Patrick Williams