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/// Marengo Cost-in-Use

Marengo is One of the Least Expensive Program Options for Weed Management

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Growers use a variety of tools to effectively manage weeds such as herbicides (pre and post), cultivation and barriers (ground cloth, mulches, etc). According to North Carolina State Extension, the cost of weed management in container nursery crops can exceed $4,000 per acre and the labor to hand weed pots continues to be a significant expense.  


One cost-effective way to reduce labor expense is the use of preemergence herbicides. When evaluating different preemergence solutions, it is important to look at the total program cost, which is best measured as cost per acre per month of control. This includes:

  • cost of product and labor for the initial application
  • cost of product and labor for clean-up
  • cost of product and labor for any reapplication treatments.

Products that are less expensive up front, but have a short residual will require more frequent reapplication and/or more clean-up between applications. This drives both labor and product costs. Products offering longer residual control will reduce the frequency for reapplication and clean-up applications because they last longer, reducing labor and product cost. No product lasts longer than Marengo, making it one of the least expensive program options for weed management based on cost per month per acre of control. 

A product that lasts up to 4 months will have to be applied twice to achieve similar results to a product that lasts up to 8 months. That means the labor cost will be twice as expensive for the shorter-lived product. Every herbicide application includes labor for:


  • site preparation
  • application prep (equipment, handling, mixing, etc.)
  • application
  • clean up (equipment, disposal, etc.)
Success with Preemergence Herbicides


Effective herbicide management begins with reading the product label. The Marengo label provides information on application timing, rates, spray volume and how to activate the herbicide. Marengo preemergence herbicide forms a continuous chemical barrier over the soil surface to which it is applied, so application uniformity will ensure adequate coverage for optimum weed control. Failure to properly calibrate herbicide application equipment will likely result in poor weed control. If the application is improperly timed (i.e. following weed seed germination), there will be a significant reduction in the level of control. Marengo should be applied to a site before weed seeds germinate to prevent weeds from emerging or developing.
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