A Biological Approach to Spring IPM ft. Koppert’s Heidi Doering

Check out the Tech On Demand podcast, featuring our very own Koppert technical consultant Heidi Doering; A Biological Approach to Sprin… - TECH ON DEMAND brought to you by GrowerTalks - Apple Podcasts

Transcript:

(0:14) Bill Calkins: Greetings, greenhouse people. We're back at it with another episode of Tech On Demand, brought to you by the fine folks at GrowerTalks magazine. If you don't receive GrowerTalks and Green Profit every month, head over to growertalks.com and subscribe. The magazine has been a pillar of the industry for more than 75 years. It's about time you join the club. And speaking of subscribing, be sure to subscribe to the Tech On Demand podcast on your favorite app, like Apple Podcasts, Spotify, Google, Odyssey, and many more.

If you have an extra minute to leave us a positive review, that would be awesome. Every little bit helps our algorithms and allows us to reach more greenhouse professionals. I'm your host, Bill Calkins, and this episode is all about spring pest control, integrated pest management, and implementing biocontrol strategies that work.

My guest is Heidi Doering, Koppert's National Ornamental Team Lead and Technical IPM Consultant for the Midwest region. Koppert is a global market leader specializing in biological crop protection, and as you'll hear in a minute, my guest Heidi has not only been with Koppert for almost 10 years, but has a broad range of horticultural experience from greenhouse production to product management and sales, which means she has a unique perspective and breadth of knowledge to find unique IPM solutions for growers wherever they're at on the continuum of chemical, biological, and hybrid approaches. In this episode, we discussed what Heidi's seeing already as spring production ramps up across North America, her role as a greenhouse CSI whenever she walks into a facility, common spring pests and potential prevention and management strategies, education and planning as they relate to biological IPM, the importance of relationships, and her thoughts on thrips parvispinus, the pepper thrips hitchhiking their way up north on tropical plants. It's a fantastic and well-rounded discussion. Before we get started, let me take a minute or two to share some of Heidi's bio because it's quite diverse and will help you understand her nuanced approach to IPM.

Heidi says she escaped the dairy farm after graduation and attended University of Wisconsin-River Falls, with Terry Ferriss as mentor and advisor, graduated with a BS in horticulture and business administration, and a minor in French. After several years working at Twin Cities cut flower wholesalers, she went back to school and earned her master's from Penn State. Then she moved to the Netherlands for five months to work for an orchid grower and then to a tree and shrub nursery in the southwest of France, probably to use that French minor, for three months through a University of Minnesota program now called MAST International. Upon returning to the U.S., she worked as a cut flower sales consultant for two wholesale flower suppliers in St. Paul, then moved into greenhouse production, becoming the head grower and producing every possible crop a florist or Midwest garden center would offer to gardeners. Curiosity and a need to continue learning and growing led her to leave greenhouse production for a product management role with Syngenta Flowers, managing cultural trials, sales forecasts, product introductions, and technical support for a number of cool crops and florist crops such as pansies, primula, cyclamen, and gerbera. As is often the case, she missed growing plants and returned to greenhouse production for a few more years before becoming a horticulture educator for University of Wisconsin Extension for three years prior to Koppert's Midwest Territory position opening up and having an opportunity to apply for the role and start with Koppert in March of 2016. As she says, the rest is history.

But that's enough out of me. Let's jump into biological pest control and spring IPM with Koppert's Heidi Doering. Heidi, welcome to Tech On Demand.

Heidi Doering: Thanks, Bill. I'm happy to be here for the first time.

Bill Calkins: Awesome. And it is great to have you as a guest. I really have liked your articles in GrowerTalks, and you've written for my newsletter now, which is exciting.

And the way that you share the information is definitely understandable and interesting and super knowledgeable, which comes a lot from your background and your history in the industry, which I covered in your bio. You really have a huge range of experience from Extension and greenhouse field production and greenhouse production. So I know that we're going to have a good conversation, especially as it relates to our topic, which is working with growers to implement effective IPM programs, spring IPM, and biocontrols.
I think that we got plenty to talk about in the next half hour or so. But I do want to start by asking you how it's going so far in 2025. I know you're talking to growers plenty and probably seeing some things happening out there in the field. What's going on out there?

Heidi Doering: Yeah, I was out in the field last week meeting with some growers, and definitely things have changed drastically since last week. We've gone from trying to get above zero degrees Fahrenheit to now we're going to be 50 tomorrow. So spring is going to jump into action really quickly here, and we're going to be in full-on insect mode in no time.

So I think folks are ready. Yeah, I think folks are ready. Although I always like to do these really early visits in the season to try to check in with each of my clients because there's always something that seems to have gotten forgotten.

And it's something that's fairly critical, something like weeds on the ground. And so just to be able to stop at a greenhouse, take a quick look around, talk with them, and then find those early-season concerns that could blow up into something a lot more serious later. And we can get that in the bud right at the beginning of the crop cycle.

Bill Calkins: Sounds good. Sounds good. And maybe we can dig into some of those things as we go.
That, I think, provides a good starting point for us. I know a lot of our listeners are busy with spring crops. I mean, if you bought in URCs, they're potted up. If you're getting liners, they're probably coming in as we speak. In some regions, we're pretty close to spring down South.

So as we think about what's going on early, I'd like to start with something you and I talked about as we were preparing for this podcast. And that's how you and the technical team at Koppert work through some of these situations all the time. And you use this term CSI. And I will credit Jeremy Weber from your team for coining that term as it relates to the way that you guys approach your clients.

And it kind of references walking into a greenhouse for the first time to help an operation implement a biocontrol strategy and how that is sort of solving mysteries and asking questions and trying to get to the bottom of things. Can you talk a little bit about that, kind of what being a CSI means in your world and what you look for when you consult with clients? For sure.

Heidi Doering: Yeah. So when we get a call from a client and they say, yeah, we need help, right away our minds just go wild. We're like, great, this is awesome. But we have to get really seriously dialed in before we can do anything. So it's asking a lot of questions.

I think what we really do the first time we talk with someone via phone, or whether we get to go there out in person and meet with them in their greenhouses, it's a look, listen, and learn is what we're doing. We're going to look around. We're going to see what kind of crops they're growing, what their facilities look like, what their environmental controls are, how much control they have or don't have.

Do they have concrete floors or dirt floors? Because that makes a complete, a large difference in our approach and our level of control needed. And then just, you know, what happened? What caused them to call us and have a little discussion about that? What caused their trauma or PTSD that made them pick up the phone and call us and say, I need help, that cry for help?

So then we'll walk into the greenhouse, take a look around, and then sit down and talk with them and discuss exactly, you know, what's the current state of affairs? Are you starting a new crop? Is this a crop that you've been growing for six, eight months, overwintered? Where are they in the crop cycle?

And then from there, we can talk about what they've done in the past and why, how it worked or didn't work. What are their goals for the future? Where would they like to be at the end of the crop cycle this year that they weren't at last year? And then from that, once we know where they've come from and where they are and where they'd like to be, then we can start to flesh out a plan to get there.

It could be just adjusting chemical controls, just doing a better job of rotating chemistries. We give out chemical recommendations all the time.

Bill Calkins: Oh, I'm sure.

Heidi Doering: Yeah. But then there's also the hybrid approach, where you start to incorporate some beneficial insects or some biological insecticides to help break pesticide resistance, or the grower's like, I'm sick of spraying. I don't ever want to put on that suit again.

That's just another whole level of control, and we can get there. But yeah, so we just need to know those things up front, and that's what gets us started.

Bill Calkins: No, that's cool. And I would imagine some of the conversations you have are recurring problems, things that they've had year after year, and they're finally to a point where they just need some help figuring out how to not deal with it again.

(10:02) Heidi Doering: Yes. And it's a matter of, yeah, has this been going on year after year? And if so, you keep doing the same thing. You get the same result every year by not changing. So you just got to get to the point where it's time to change.

And it's interesting that oftentimes now I'm seeing that there's a generational change in businesses. And with that generational change, there seems to be a point where it makes sense to start talking about bios because dad, people my age, we sprayed all the time. We didn't think anything of it. But the next generations aren't interested in spraying, putting on a spray suit every week, or sometimes twice a week if you get into some crops where there's a lot of pesticide resistance and a lot of insect pressure. And yeah, a lot of people don't want to do that anymore.

Bill Calkins: So yeah, gone are the days of we spray on Tuesdays. I mean, I think that it's so much more targeted and strategic, and you're right. It's that hybrid approach or the biological approach. And that's where you guys come into play, right, is to give that kind of advice.

I do like the CSI angle. I think it makes a lot of sense. I think a lot of specialists in our industry probably feel like, yeah, I'm a CSI every day trying to figure out what's going on with unique crops and unique greenhouses and unique people.

Heidi Doering: We're half CSI and then half Sherpas once we get started. We're there to bring the grower to the top of the mountain. We'll carry the heavy load for them.

Bill Calkins: Exactly. And then maybe not get all the glory that they get, like a Sherpa. I do think every grower has their unique approaches to crop production, but I'm sure that there are a lot of commonalities.
And I'm really interested in hearing a little bit about how you focus on some of the most common spring pests that growers deal with year to year, some of the ones that you expect to encounter in 2025 again. I guess, how do you want to approach the usual suspects? I mean, if you want to talk about them insect by insect or solutions, I'm open to however you want to approach it, but I do want to dig into some of these most common pests that growers are dealing with.

Heidi Doering: We could do insect by insect for just a few of the major ones, like aphids, fungus gnats, thrips, perhaps.

Bill Calkins: Sure. Sounds good. However you want to start. Go for it.

Heidi Doering: Sure. So I guess initially it involves a visit to their chemical cabinet. That's number one. Before I even start with any insect and biological potential, we need to see what they've been spraying and when the last time something was sprayed. If it's a new spring crop, we don't really need to worry too much about that. We could start right in.

And if it's a crop that's been in production for some time, if it's a flower crop or foliage, tropical foliage, things like that, that have been in production for eight, 10 months, that's a major concern. So in 2024, there was considerable trauma from growers. I would call it PTSD aphids, but nothing would kill them.
They were so pesticide resistant. And this was something new to a lot of growers because they've been rotating chemistries as instructed and doing what they thought was right. And now the insect pests are getting past those chemistries. And so now we have to just discuss, how do you want to go about it? Because aphids is not typically the insect that I would start with for biocontrol because we have all these tools available to us.

So typically I'll start growers out controlling fungus gnats, thrips, and spider mites, and then we'll just use chemical controls, biocompatible chemistries, to manage aphids. But I think that's totally changed this year because of Myzus 2.0, let's call it, green peach aphid that won't die. So in that case, then we just discuss the options in which parasitic wasps or predators are going to fit their crop type the best and move from there and how they'll work into the other insect pests that we're also controlling for.

Bill Calkins: Okay. And when you look at them, like how many different biocontrols do you guys have that can go after those kind of pests in a greenhouse? I know your catalog is huge.

And that's the first time I've thought about how many different biocontrol agents that you have, and that you might use them differently in different situations.

Heidi Doering: Sure. Yes. There's parasitic wasps. We have predatory bugs that are like Chrysopa, Chrysoperla, lacewing larvae, lacewing adults. There's generalists like Geocoris, things like that, that we don't typically use for aphids, but it's out there. It's a possibility.

And then there's the gall midges, Aphidoletes. And so you have a number of different options. And the choice that we make of which one to use is really based on a couple different factors: the greenhouse, the environment, the crop that it's going to be on, and the aphid species or multiple species. So there's a lot of decision-making that goes on, and there's your CSI with the first insect pest.

Bill Calkins: How about fungus gnats? What's the normal approach to managing or dealing with fungus gnats? Because I know that, I mean, every greenhouse has dealt with them at some point, and some year after year.

Heidi Doering: Yes. Fungus gnats are, there's a pretty basic approach to fungus gnats because they're relatively easy to kill when you're using biocontrols. They can be difficult to kill if you're using chemical controls, just because that adult stage isn't easy to kill.

You want to attack both the larval stage in the media, the growing media or the ground, whatever you're growing in. And you want to attack the adults that are flying or coming up out of the ground as well, because each insect pest, you want to break that life cycle in as many places as you can at once to collapse it. And if you only put in, say, so we have nematodes, we have soil-dwelling predatory mites, and we have entomopathogenic fungi like Isaria fumosorosea that are all effective to kill some one or two stages of fungus gnats.

But if you only use one of those tools, you may not achieve the control that you need. So by combining nematodes plus Isaria, then you are breaking both the adult life cycle with the beneficial fungi and the larval stage with the nematodes.

Bill Calkins: Okay, that makes sense.

Heidi Doering: And with fungus gnats, there's one more detail that's kind of a critical piece, is are they growing, is the crop something that can be grown wet, or does it need to stay on the drier side? And so if it's something that the roots will be damaged, or you'll get root pathogens if it stays too wet, then we may want to use the soil-dwelling predatory mites, because then you're applying those as a dry material, and the predatory mites are living in there without having to reapply weekly and add more moisture.

Bill Calkins: That makes sense, because you do have, I mean, your approach would be different based on the crop type. Okay.

Heidi Doering: Intolerance for moisture.

Bill Calkins: How about thrips? Because that's one that growers will encounter really in all seasons. I mean, you encounter plenty of thrips in the fall when you're growing poinsettias too.

Heidi Doering: Yes, and for thrips, they're coming into the greenhouse in a number of different ways. This past week I did see some concerns with thrips coming in on cuttings, on cutting material from material that was produced in the U.S. here at a greenhouse, and then I see a lot of times the calls coming from within the house. So I'll look down and see some pigweed and pick it up, and there's thrips all over it.

Bill Calkins: Okay.

Heidi Doering: And like last week I saw one leaf that had whitefly, echinothrips, and spider mite on it all at the same time.

Bill Calkins: Oh, and an aphid as well.

Heidi Doering: Oh, wow. It's all on the same leaf. So this is a retail garden center that stays open all winter, doesn't close down. So it's very common to see this.

But for thrips especially, if they're coming from within the greenhouse, it's really important to get that cleaned up before you start bringing in new material or you're just reinvesting an already infested greenhouse. So those details can become important. But then going forward for thrips, once you have that conversation about weed control management and getting rid of that, then we're looking at predatory mites.

There's a number of different predatory mites we can use that will attack the L1 and L2 stage in the case of Limonicus, but most are attacking just the first larval stage when it's on the leaf. And then you've got your soil-dwelling predatory mites, Stratiolaelaps, and nematodes will impact both pupal stage in the soil. And so that can be a dual control when you're controlling for fungus gnats and thrips at the same time with those two strategies.

And then for the thrips adults, we've got a couple different options. This time of year, it's a little bit early to be using Orius, but Orius is an amazing tool for later in the season or if you're lighting the crop or if conditions are right. And then the other is the beneficial fungi, the Isarid, again, because that will penetrate the cuticle of the thrips and kill it as well.

Bill Calkins: What are, are there any other usual suspects you want to talk about, or are those the main ones?

Heidi Doering: The other one that I guess I hear, well, we've got spider mites, or we have mealybugs would be the other two.

Bill Calkins: Okay.

Heidi Doering: Spider mites are pretty straightforward. If you have them, if you haven't been spraying broad-spectrum chemistries that will leave a residual on the leaves, we can come in with Persimilis and/or Californicus and take care of those infestations fairly easily. We say that with a grain of salt, but for sure that's kind of the most straightforward insect pest that we can control because all life stages are on the leaf at once.

And so something like Persimilis attacks all life stages of spider mite, and two-spotted spider mite in particular. So we can easily target that. And then I guess in this breath I could mention broad mite as well. Last year was quite a hard year for broad mite as well.

Bill Calkins: Yeah.

Heidi Doering: And so I expect we won't see it much this year. The farms are probably much more vigilant this year in maintaining it, but it is something that is present at the stock farms. So it is a challenge for them to manage. It's endemic there. So it's something that should be on our radar, especially for New Guinea impatiens and some of those crops that they really like, begonias, varieties of begonias, things like that.

Bill Calkins: So what's the first approach? Is it similar to spider mites, or...?

(20:22) Heidi Doering: Broad mite is a totally different animal, insect, different mite than spider mite. So we approach it differently because it's something that can, there's not a lot of beneficial insects that want to attack and eat it.

Not your preferred species. It's like the liver of the insect world. So we need to either knock it down with something early on before we plant the pot and grow the plants, or you can come in with a really high rate of predatory mites, but then it's the economics of it that get a little challenging. So it's much more economical and protective, I'd say, of the crop to spray it with a biocompatible or nearly biocompatible insecticide before you start applying beneficials. Something that has a short residual of one to two weeks, predatory mites after that.

Bill Calkins: Did you want to touch on mealybugs? I mean, it's definitely...

Heidi Doerin: Mealybugs, I'll just say, that's another one like aphids that the call may be coming from within the house. So, you know, if your growers are overwintering pet plants...

Bill Calkins: Oh, okay.

Heidi Doering: Yeah.

Bill Calkins: Not uncommon.

Heidi Doering: Yeah. Beautiful, beautiful plants in the greenhouse. I saw a flamingo last week, flowering, full flower. It looks great. But just thrips raining down off of it.

Bill Calkins: Yeah.

Heidi Doering: So those types of pet plants will oftentimes harbor mealybug, or slow-growing crops such as succulents are oftentimes a sink, or a place for mealybugs to hang out. And they're not really noticed until you start adding other plant material to the greenhouse.

Bill Calkins: Yeah.

Heidi Doering: And they're on benches right next to the mealybug, and all of a sudden now another crop has mealybug on it as well. So, and again, they're a little tricky to control because mom, especially with citrus mealybugs, mom's protecting her babies underneath her. So you can only target what you can reach.
So the product will infect and kill the nymph, the crawlers, but it's not going to take out mom with her waxy coating. Mealybugs require a situation to keep applying. If you're going to use a hybrid approach of chemistries and biologicals, if you're going to use biologicals, then you're looking at the mealybug destroyer, Cryptolaemus, or lacewing larvae as a tool. But for most growers, that's a little bit more of an expensive type of control. So we kind of steer toward chemistries, especially because mealybugs are so hard to clean up when they're in crops like Dracaena, where they have leaf folds and they get down in those leaf folds, and it's really difficult to eliminate them from a crop unless you use chemistries.

Bill Calkins: Well, and it sounds like, I mean, your best strategy for control is to avoid the problem in the first place by not keeping pet plants, by not, you know, by keeping an eye on those long crops like succulents that you just sat down and kind of forget about, but they certainly might be harboring some problems. And I think that's a good segue to kind of the way that you and the team approach growers and building those relationships because, I mean, we can talk about being a CSI, but part of that is really understanding the, I guess, the partnership that you're in with that grower. And I know that you guys are in it for the long haul.

When I did a two-part podcast with Jeremy Weber, we talked about that a lot, and I'll put a link to that in the show notes, and that Koppert has a long, long history. You guys have been doing this a long time in horticulture and agriculture and CEA. Learning more about these long-term relationships is always interesting for me because when I think about biocontrols, I think the learning curve can be fairly steep for a lot of growers who've been kind of taking a traditional approach in the past. So what are some of the first steps a grower or an operation can take to prepare for the hybrid approach that you talked about or an eventual shift to a majority biological strategy?

I would imagine, I think of it as kind of a crawl, walk, run. You might think of it differently, but how do you approach that relationship when you first start meeting with a client who's looking to make some changes?

Heidi Doering: I like the crawl, walk, run metaphor definitely. And I'll expand upon that in a minute, but I would say the first advice I give growers as they're looking to make these changes is definitely crawl before anything. You don't want to jump into an entire facility and try to go biocontrol 100 percent the first year. You want to test it in a crop or in a greenhouse where you know you're having problems and you're really struggling.

At that point, we can dial in controls and strategies to support that. It's manageable enough that the grower will see the results, and if it starts to go off the rails, it's easy enough to bring it back on the tracks. Whereas if you have a larger facility, they start 100 percent bio, it's going to be really hard to keep up with that, just the learning curve.

Because in the crawling phase, we're visiting that grower, we're talking with them, looking at their pesticide storage, talking about which IRAC groups they've been using in the past or they currently have available that will be biocompatible. Are they familiar with some of those biocompatible things that we might need to pull out of the cabinet and use to save the crop in case something goes sideways? Or a population of thrips blows in in early May, and all of a sudden their cards are showing a thousand thrips instead of the typical three or four in a week. That can cause some serious panic.

We just want to make sure growers are comfortable with that level of risk and involvement in that. And then we can walk through the greenhouse, walk through their goals, like I said earlier on. What do they want to get out of it at the end of this? What will success look like to them? And then from there we can assess and then decide whether the next season we expand it, adjust it, or scrap it and start over and do something different.

Bill Calkins: What are some red flags that you see when you have that first initial discussion? You talked about going to the chemical cabinet. Is there a time when you would say, hey, we got to hold off for a month, or we've got to make some changes first before we bring in any sort of a biocontrol?

If a grower is listening to this and thinking, oh, you know, this is definitely a direction I want to move in, what are some of those early changes that they can make to be a little bit more prepared for that conversation and those next steps?

Heidi Doering: I'd say the number one thing, if they've been using traditional chemistries up until now and are starting from that level of IPM, they really need to consider what they've been using and change that. If it's broad-spectrum materials, things from IRAC group 1, 2, 3, and 4, several of those, for instance bifenthrin has a 12- to 15-week negative persistence against the beneficial insects.

So when I'm asking them what they've been using or what they have in the cabinet, they might pull out bifenthrin first. If that's one of the tools that they like to rely on, then we need to have a little conversation and say that's either got to go out of the greenhouse or it needs to be set aside somewhere where it's called Heidi before applying. And so that's one of those conversations. And mostly, I can explain to them how this particular AI is going to be detrimental to the overall plan, and if they want to move forward, we need to work together as a partnership.

And I'll provide the technical support, but then they have to back it up with the actual actions. It's a definite teamwork to make this all happen.

Bill Calkins: Now, that's cool. And you've worked with enough growers over your career and the team at Koppert that I'm sure you can work with anyone to move in the direction that they want to go, but the timeline will just look different, I guess, for every operation.

Heidi Doering: Yep, exactly. Yeah, I've worked with breeding companies, for instance. They have no tolerance for insect pests.

Bill Calkins: Right.

Heidi Doering: So when I go in to visit them the first time, they have no tolerance for insect pests. So they're spraying once or twice a week with broad spectrum, everything. But then when I go in the crop and look, there's insect pests. So it's a matter of having that discussion, like, is this really working for you or not? And then once they realize, oh, maybe it isn't working, then just ramping it down.

But if they've applied something really persistent, then we just need to do a step-down of chemistries to go 12 weeks, 10 weeks, eight weeks, six weeks. When you get down to about two weeks, then we're almost using exclusively biocompatible products, like maybe it's soaps or oils if it's spider mites, or it may be things like Mainspring, Pradia, Altus, different thrips controls. But then when we get to that one week, then we can start applying.

Bill Calkins: And I know from just my own going to sessions and hearing experts talk that the opportunity for biocontrols or a hybrid approach is really available to anybody, no matter your greenhouse size or what you're growing. A lot of it does come down to knowing what you've been using and making a commitment to reduce some of that and take a different mindset. How much of it is kind of a mindset of the grower or the production team? How much does that factor in, do you think, to how successful they're going to be with a biocontrol strategy?

Heidi Doering: Mindset is huge. There's the mindset of the owner, there's the mindset of the production manager, and then the mindset of the growers who are boots on the ground, and those all need to align for it to work. Yes, so you can have a grower that's like, yes, I want to use bios. Production manager's like, well, what is it going to look like on the budget? And then you talk to the owner. Oh no, everything's working fine. We don't need to make any changes.

So it's a matter of getting everybody in the room together sometimes and having a frank conversation. Like, is it really working? Do you remember throwing away that acre of garden mums last summer because broad mites were pesticide resistant and nothing would work on them? And what would it be worth to you if that didn't happen again? So, you know, and that's where everybody across the production facility better understands, oh yeah, maybe it was a problem. I didn't realize it, but it did hit our bottom line. So then it becomes more important to the owner.

Bill Calkins: Yeah, yeah. That's the pain point that hits the owner for sure.

Heidi Doering: Sure. Yeah, last week when I talked to a grower, they had, like I said, it was a tough aphid year last year, and they had aphids populate so rapidly and so extensively that they were flipping and dipping the plants in soap before they could pack them and ship them. It was so, yeah. I mean, so it can happen really fast. You know, it's like pests, and growers are busy in the springtime. It's hard to manage it all. So it can sneak up really fast if conditions are right, and then you just don't want that to happen again.
So are we going to use just a different chemistry for it? Looking at the hybrid approach, biologicals, we can do anything custom. And they saw the labor cost of that and the inefficiency of it.

Bill Calkins: I would imagine that opens their minds to, you know, man, there's got to be a different way to tackle this.

Heidi Doering: Yeah. Another example is last year, it's always interesting watching tropical foliage come up from Florida. Spider mites are so difficult to control down there, and they struggle with it. They're doing what they can, but it's a tough pest. So when they get up here, finished flowering tropicals, all of a sudden now we've got to deal with this on the northern half of the U.S. for retail garden center use.

And if you just leave it and don't pay attention to it, you'll have dead plants in four weeks. Growers have called me and said, what can we do to get past this, to kill these spider mites? And the thrips are also pesticide resistant as well. And then they'll come with aphids on them and mealybug, everything. One grower actually did a baptism. He mixed up Aphishield in a big 55-gallon drum, and he flipped plants upside down and dunked each one individually, and the labor of that was worthwhile for him as he understood that now they wouldn't lose plants. Now, from this place on, they managed that spider mite.

Bill Calkins: That's an interesting story, and the dollar and the value of those crops is so high. I mean, it's very different than a plug tray at that point. So when you lose one...

Heidi Doering:That's for sure.

Bill Calkins: Well, and again, you provided a perfect segue to a question I've got to ask you before we wrap up, and it's kind of a hot topic. It was last year. I know that we're going to hear more about it this year. And that's the thrips parvispinus, the pepper thrips that we heard so much about in 2024. I know it's been making its way. I know that there's a lot of research being done on control strategies. I also know from talking to you and some of the folks on your team that you guys do have a strategy to deal with this problem.

But I'm interested, what do you think the risk is this spring and summer, and what kind of a recipe you would take to a grower who is having challenges or saw it last year or was worried about it this year? I don't know. Give me your thoughts on thrips parvispinus.

Heidi Doering: Yeah, this one's a gnarly one. And Florida growers, they're going to fight for their lives with this insect pest. It's really been tough on them, and just like snowbirds get in their car and they drive from Florida up to Minnesota, yeah, parvispinus is doing that same thing and coming up to the Midwest, the Northeast, and Mid-Atlantic to garden centers. And so we need to be able to do something against that.
Now unfortunately those plants have had a lot of pesticide sprayed on them for the past nine to 10 months, so we're not going to be able to use something like Limonicus on it. But Limonicus is definitely, it's an animal, it's a beast, and it'll attack both the first and second larval stages of thrips. And it's a type 3 predatory mite. So it's also going to attack whitefly, spider mite, so it's got, it's a nice broad-spectrum predatory mite.

But in this case we can't use that in here because we have these residues on the plants. So in that case we're going to use things like the Isarid, your biological insecticide. You're going to use soaps, oils, anything that's not a chemical AI. So we have to stay away from anything that's a chemical AI because they're likely going to be resistant to it. I've got a cleanup protocol that I'll share with retail garden centers as they call and ask for that, to try to help clean those plants up in the two or three weeks between the time they get them and the time they open up the retail stores.

Bill Calkins: So do you think that it's going to be an issue again in 2025?

Heidi Doering: It's not going away, and absolutely it's going to be an issue this spring. And then in terms of Limonicus helping out, that's really going to kick into gear when we get to next year's crop, okay? We're going to be able to meet with Florida growers and get into greenhouses in Florida to support them however they need and at whatever level they're looking to do or are able to, with the kinds of facilities and growing situations that they have.

Moving into that area, because for growers who are doing mandevillas, hibiscus, gardenias, it's been really hard. And those parvispinus, when they get up to Minnesota and unload the greenhouse and then those mandevillas are gone, but now garden mums just got moved into that greenhouse, and they love mums. So I've seen garden mum crops destroyed by them up north.

So it's really something we have to have on our radar. We have to support growers to find solutions, and Koppert is dedicated to that with our R&D and finding which predatory mites are going to work best and then making sure those are available to growers with the technical support.

Bill Calkins: It's good to hear. I think that'll help growers feel a little bit more, a little bit less trauma in the future, for sure.

Heidi Doering: Yeah. And it's not just Limonicus that's doing the work, but they're doing the heavy lifting. And then we have the other things, like the nematodes and Isaria, are doing a lot of the work too. It's a group effort from all of our biological tools, just like nature, right? I mean, kind of makes sense. Create an ecosystem.

Bill Calkins: Oh, that's cool. This has been a great conversation. I really do appreciate your time. Before we close, I always like to let my guests kind of, you know, what have we missed? Because I know that, you know, we talked about a lot of topics, but is there any advice you want to give or anything that you want to make sure to reiterate or share with the listeners before we close? Now is that time.

(29:47) Heidi Doering: I guess what I would want to say is, if you see something, say something. Growers oftentimes, maybe aren't looking. But if you see an aphid or thrips damage or you see anything, just in initial stages, or even think about it, look closer.

Because a lot of these issues could be stopped or reversed or addressed early on in the crop cycle. But like for instance, fungus gnats, if they're not controlled when you have three or four fungus gnats on your weekly sticky cards, in two or three weeks you're going to have hundreds on there, and now you have damaged roots and damaged plants. So don't wait, don't hesitate, pick up the phone and call us. There's no silly questions. We're here to help, but we need to get the phone call or the text or the pictures via email to be able to help. And we're happy to help. That's what we're here for.

Bill Calkins: That's cool. And that brings me to my next question, which is for the listeners, how can they reach out? What are some ways that they can learn more about the solutions from Koppert or your team of specialists? Because I know you've got some really, really experienced and dedicated people out there in the field.

Heidi Doering: Yes, I would recommend going to koppertus.com. We've got a page there that shows a map of the U.S., and on that map you can click on the icon closest to your state, and that's a Koppert technical sales consultant in your area. The other way would be to just click on the general contact us, and that will go into the office, and then they'll send that out to each of us.

Bill Calkins: Perfect. I'll put links to all of that in the show notes for the listeners. We'll keep it one click away. And I know that you guys also have fantastic resources online, videos, charts, I mean, all sorts of educational resources to help folks get a little bit more, I guess, familiar with the product and the approaches, learn a little bit more about your team even before they reach out.

I know that I've binge-watched some of your videos in the past, and the amount of information there really is amazing. So I will make sure to include all of those links. But Heidi, I really appreciate it. I appreciate all the work that you guys do. I appreciate what you're doing to help us at GrowerTalks share information with growers, and then just your overall approach to helping growers and truly being a partner. So thank you so much for what you do.

Heidi Doering: Yeah, this has been fun.

Bill Calkins: Awesome. And I know that we will talk again. You will read Heidi's articles more and more. You'll see them in my newsletter, and I look forward to continuing our relationship. So thank you so much.

Heidi Doering: You're welcome. And I'm looking forward to it as well.

Bill Calkins: Sounds good. Thanks, Heidi.

Heidi Doering: All right. Thanks, Bill.

RESOURCES:

Koppert U.S. 

Koppert Consultants & Locations

Koppert Crop Protection Products

2024 GrowerTalks Biosolutions Guide

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