Greenhouse Management: What are some of the key benefits provided by Marengo herbicide for greenhouse ornamental growers?

Aaron Palmateer, Ph.D.: Greenhouses that do a good job of managing weeds are laser focused on controlling them at their source, and Marengo offers a cost-effective option to accomplish this. Marengo is a selective, preemergence herbicide that will control 98 different weed species including broadleaves, grasses, and annual sedges, providing up to eight months of control from a single application. The active ingredient in Marengo — indaziflam — has a unique mode of action making it ideal for rotation and weed resistance management. Marengo is labeled and can be safely used inside the greenhouse to provide bare ground weed control beneath benches and potted plants where weeds may germinate.

GM: What recommendations do you have for applying Marengo in greenhouses?

AP: For optimum results, apply Marengo before weed seed germinates. When weeds are already present, add a postemergence herbicide specified by the label. If fans are present, turn them off during an application. Applicators can treat cracks or crevices in concrete floors or other impervious surfaces where weeds are likely to grow. Do not allow Marengo to puddle or pool, especially where potted plants will be placed. When treating greenhouse floors and areas around potted plants (i.e. under benches), try to minimize direct contact with the foliage of desirable plants. If the spray does contact the plant canopy be sure to rinse it off the plants before it dries. A light irrigation event after application will help to activate Marengo prior to weed germination.

“A single application of Marengo allows for greenhouse growers to focus their time and effort on other factors besides weeds for up to eight months.” — Aaron Palmateer

GM: What is Marengo’s re-entry interval and how does it allow crews to get back into the growing bays and working again?

AP: Marengo has no signal word on the label and offers a 12-hour restricted entry interval. However, workers can enter treated areas of the greenhouse at any time if wearing coveralls, waterproof gloves and shoes plus socks.

GM: What are some other key characteristics of Marengo that growers seek?

AP: When it comes to weed control inside of greenhouses or other enclosed structures, preemergence herbicide options are limited. Greenhouse growers look to Marengo for convenience, because they can apply it inside the greenhouse when plants are present. This characteristic separates Marengo from other preemergence herbicides where applications can be made only in the absence of plants. A single application of Marengo allows for greenhouse growers to focus their time and effort on other factors besides weeds for up to eight months. This long-lasting residual control reduces the frequency of reapplication and clean-up applications, reducing labor and product costs and ultimately making Marengo a cost-effective solution for controlling weeds in the greenhouse.

Greenhouse Management: Where does BASF suggest ornamental growers begin when building their insecticide programs for the Spring season?

Jen Browning: Try focusing on functional groups. This makes for a simple way to write an insecticide program. You have five main functional groups when you think about insecticides — oils and soaps, insect growth regulators (IGRs), biological insecticides, targeted conventionals and broad-spectrum conventionals.

Oils and soaps will help disrupt the life cycle of most insects and mites to help delay resistance. Look for highly purified oils, (99% unsulfonated residue) for maximum plant safety under the widest range of growing conditions. IGRs also help with disrupting the life cycle of pests, typically by preventing juveniles from maturing into reproductive adults. Each reproductive adult you remove from the population prevents all their offspring from feeding on your plants, so the effect is magnified.

Even if you don’t run a full biologicals program and think that approach isn’t for you, biological insecticides can enhance the results you get with the rest of your program in sprays you’re going to be making anyway.

Targeted conventionals are great for growers who want to preserve beneficials in their ranges, indoor or outdoor, that are providing them with some biological control as predators or parasitoids.

Broad-spectrum conventionals are the “old school” workhorses of the chemical shed. We’ve lost some of these materials over the years, and the ones we have left must be stewarded carefully because they have an important role in our integrated pest management (IPM) programs.

Why does focusing on functional groups simplify the decision-making process for integrated pest management (IPM) in greenhouses?

JB: Choosing solutions from the functional groups for your pests of interest will automatically start the process of rotating your modes of action (MOAs). It simplifies the process of product selection and can keep you from buying redundant products or missing a key functional group that is a heavy lifter in managing difficult pests.

How has the way growers use broad-spectrum conventionals changed over time?

JB: We tend to not use broad-spectrum conventionals the way we used to for every application and without much thought, but we want to have access to them for the important job they do when we need that hammer. Sometimes you’ll need a rescue application at the height of summer when populations are extremely high, for a difficult or large-bodied pest you can’t otherwise control, or when you need to do a clean-up application prior to changing crops in a range.

What are some of the newer approaches growers are trying in their IPM programs?

JB: Targeted conventionals are the newer generation of conventional chemistries. These active ingredients may cover several groups of insects or mites or they may be very specific, such as Sultan® miticide, which only kills spider mites (Tetranychidae), but not mites in other families. The greatest benefit to these types of chemistries is that many of them preserve beneficials and have better pollinator and non-target safety. The trade-off is that you’ll need to be sure of your pest identification. If you spray broad mites (Tarsonemidae) with a spider-mite-specific product, you won’t see any control.

Which functional group should growers use to reduce everyday ornamental challenges?

JB: Biological insecticides work best for foundational applications made weekly to keep greenhouse pest pressures low. These products can include Beauveria bassiana insecticides like Velifer® fungal contact insecticide/miticide or Nemasys® and Millenium® beneficial nematodes.

Greenhouse Management: What trends do you see in the overall calibrachoa market?

Mike Fernandez, market manager — North America: The trend is to breed for early to flower varieties that have tighter internodes to promote more flowering and better branching. Also, breeding for pH sensitivity and always for larger more colorful flowers. All these things will provide a better experience for the end consumer.

GM: What sets Danziger calibrachoa breeding apart from the others?

MF: I believe what sets Danziger apart from others is the location of our breeding. All varieties are bred in Israel and this gives us an advantage for heat tolerant varieties. I also believe that our trialing and testing process around the world gives us more data before introduction. Having our own labs for diagnostics, TC supply and R&D is also a huge advantage. All of these things combined enable us to go to market confident in the introduction. Additionally, having our own supply chain for each market helps to add value for our customers.

GM: What exciting new innovations in this crop does Danziger have in the pipeline for the future?

MF: I believe one of the most exciting things is our initiative to breed controlled growth products. Controlled growth means a plant that grows and looks like it has had plant growth regulators (PGR) but it hasn’t. This will make easier to grow varieties for the grower and a better-quality plant overall. It also lengthens shelf life which is very important to both the grower and retailer. We also have more unique novelties in the pipeline. These are always appealing to consumers.

GM: How can a grower fit these products into their current offerings?

MF: The best way is through trialing. Danziger makes all varieties available for trial free of charge because we believe that this is the best way for the grower to know if it will work for them. Another important factor is for the grower to attend regional trials to see the varieties growing in their own area. Danziger is making a list of these trials available to all growers so that they will know where they can see our genetics at unbiased regional trials.

GM: What can growers do to finish the best cali crop possible?

MF: Although the breeding is for the varieties to be able to tolerate a higher pH, it is still important to know your water pH and alkalinity so you can make the best decision on fertilizer and acid injection as necessary. A good scouting program for insects and pH testing are also key. Knowing the finish timing, correct PGR rates for each variety, overall habit and vigor is all important for finishing a strong and marketable plant.

Greenhouse Management: To what developments do you attribute the recent increase in interest in automation and moving plants via conveyor systems?

Edwin Dijkshoorn: There is more and more interest in conveyor belt systems because of labor shortages as well as the seasonality of the industry. You’re highly dependent on seasonal labor. They say today in the U.S. there are 9.7 million people unemployed, but nobody seems to be able to find good workers right now. This is not just growers either, it goes across most industries. Wages are also going up, too, and with the cost of some of the equipment going down, there is a much faster return on investment today when it comes to automation technologies.

GM: Why do you think U.S. operations have trended a bit behind their European counterparts when it comes to adopting automation in the greenhouse?

ED: In Europe there is a lot of mono cropping. Many of the largest growers produce only one crop or variety, so the labor cycle is more fixed than over here where a lot of the growers are producing multiple crops in the same greenhouse. The mono-cropping makes automation much easier to adapt to your workflow because your employees are completing the same tasks pretty much every day. And then, again, the seasonality of how we grow here in the U.S., as well as all of the different products that these growers are required to use when they produce a crop for the big-box retailers, it can become quite overwhelming for some of them.

“It is all about eliminating plant touches and people steps where you can, and where it makes sense too.” -Edwin Dijkshoorn

GM: Tell us about your SmartFlo 300 system and how it can enable a grower to be more efficient.

ED: It is all about eliminating plant touches and people steps where you can, and where it makes sense too. Here in the U.S. you have greenhouse operations moving plants and/or products in and out of the greenhouse and into the different production bays at a rapid pace. Normally that requires a train of moveable carts and you have employees picking up the plants two at a time and walking them over to the carts. Once the carts are full, they drive the carts to another bay and they unload and space them back onto the floor. With a conveyor system we can eliminate a lot of those touch points and miles walked. The plants now meet the worker in the workspace. It’s much more efficient and it also provides the grower with peace of mind.

GM: Do you have any parting tips for growers who are thinking about adding conveyors but haven’t done so yet?

ED: Take a 30,000-foot view of your operation and how often you or your workers are touching plants, and how often they are waking to and from plant handlings. Also consider the possibilities. There are a lot of growers expanding right now and building brand new greenhouses, but maybe you are not using the space you already have as efficiently as possible and consolidating crops with conveyors would improve this. Instead of building these big, expensive new greenhouses all the time, you might already have enough space.