Expert solutions

Envu Ornamentals business and its Green Solutions Team (GST) are committed to providing guidance that helps growers save time and money. To continue that pledge, the GST added plant pathologist Janna Beckerman to provide technical support for greenhouse and nursery growers. Beckerman joins Envu after 20 years at Purdue University as a professor and extension specialist. The GST aids growers with all their plant health needs, including weed control and herbicide use.

And Greenhouse Management caught up with Beckerman to learn more about how Marengo® herbicide is part of that collection of solutions.

Greenhouse Management: Describe Marengo herbicide and how it’s used.

Janna Beckerman: It’s interesting that prior to joining Envu in my time as a plant pathologist, I knew about Marengo herbicide. It is definitely an industry standard. It’s a selective, preemergence herbicide that can control approximately 100 different weeds. And it can do this in one application, which is just incredible.

And even more interesting, it’s doing this with a single molecule, indaziflam, a Group 29 herbicide. It comes in two formulations: liquid (Marengo® SC herbicide) and granular (Marengo® G herbicide). It controls so many different weeds and plays nice with other herbicides — that’s a win-win.

It’s labeled for use inside the greenhouse, in addition to hoop houses, lathe houses and shade houses. It can be applied to greenhouse floors prior to production, or if you use it during production, apply it underneath the benches. It’s also labeled for field-grown, pot-in-pot ornamentals and ornamental production sites.

GM: What are some of the benefits of Marengo herbicide?

JB: One application of Marengo SC herbicide can last up to eight months. If you used Marengo SC herbicide at the 18½- fluid-ounce rate, that would give you season-long control. It’s not just an herbicide that controls weeds — it frees up your bandwidth. If you only have to do one application, that’s one less thing you have to think about for at least eight months.

Labor is the most important issue that every grower is dealing with now. And this product frees up your labor and allows you to better deploy them for other tasks besides weed management — like disease and insect management!

If you’re applying Marengo herbicide in an outdoor production environment, it provides broad-spectrum control of both grassy and broadleaf weeds, even during the rainy season.

It also persists really well, despite the crazy weather we all seem to get.

Lastly, it has no signal word, meaning applicators can enter wearing coveralls, waterproof gloves and shoes with socks, and with a 12-hour reentry interval.

It easily feeds into any weed management and herbicide rotation program. Marengo herbicide gives you so much flexibility with the single molecule and it’s persistent.

GM: What stands out to you most about Marengo herbicide?

JB: As a scientist, I’m completely impressed by the fact that Marengo herbicide accomplishes all of this control with a single molecule. And this one molecule provides control of broadleaf weeds, some annual sedges and grasses. It has outstanding crop safety. The fact that it lasts for so long also stands out to me. All these things make it so different compared to other products on the market.

GM: How has Marengo herbicide made a difference for customers?

JB: For growers who have both indoor and outdoor production, Marengo herbicide works for both sites. As I mentioned, it frees up labor to perform other tasks, saving time and money for the grower.

It’s effective for a total plant health approach. When you control the weeds, you also control certain insects and some of the diseases they vector.

GM: In which situations would you recommend Marengo herbicide?

JB: I can’t think of a situation in which I would not recommend it. If you don’t need eight months of control, you can get three or four months of control with the granular formulation or a reduced rate of the flowable. I want growers to see how really cost-effective Marengo herbicide is. Because of its efficacy and persistence, you can focus your labor in other areas around the greenhouse or nursery.