4 Reasons to Rely on Preemergence Soybean Herbicides

Protecting soybean yield starts before the seed goes into the ground, making preemergence herbicide applications critical to the crop’s success. By preventing weeds from germinating and reducing competition with the crop, preemergence herbicides help soybeans get a strong start. Let’s look deeper at how they can help you get a successful start to the season. 

Benefits of Preemergence Soybean Herbicides

Preemergence herbicides aren’t new, but they may be underutilized. Unfortunately, relying on a postemergence-only herbicide strategy no longer works for most growers. As weed resistance evolves, incorporating preemergence herbicides is one effective way to keep fields clean season-long. Here are a few ways they can benefit you this season:
 

1.    They give you more options.

Using a basket-and-thimble analogy when thinking of season-long weed control in soybeans,here are many more options for managing preemergence weeds than postemergence ones. Using the basket of options available for preemergence control can help you use the thimble-sized postemergence options more effectively. 
 

2.    They buy you time.

Preemergence herbicides are a great way to keep fields clean during a critical period of weed control. That’s generally the period from seedling emergence to canopy closure when weeds can cause the most threat to yield potential. Layering residual preemergence herbicides can  help provide extended weed control after planting, which aids in smaller and more manageable weeds when it’s time to apply your postemergence application.   
 

3.    They take the pressure off.

When residual preemergence herbicides are applied, there is less pressure on the postemergence application to control emerged weeds. That enhances overall weed control and helps steward postemergence chemistries by incorporating other effective modes of action into the herbicide program.  
 

4.    They help maximize yield potential.

With fewer weeds to compete with during the critical period of weed control, soybeans get a stronger start to help maximize the growing season and build more yield. 
 

Best Practices for Preemergence Weed Control

The dollars you spend on preemergence herbicides can have a positive impact on your soybean weed control strategy so be sure you have a solid plan in place. Here are a few tips to help realize your ROI potential:

Diversify products

An effective soybean preemergence strategy includes burndown and layered residual herbicides. Start with burndown products to remove emerged weeds and follow up with layered residuals to provide extended weed control and prevent weeds from emerging before and after planting. 

Use multiple modes of action

Be sure to use preemergence herbicides with different modes of action to manage a broad spectrum of weeds and improve control. Overusing the same modes of action can lead to faster development of herbicide-resistant weed populations. Consider layering products from different herbicide groups for a broad-spectrum preemergence program. 

Make timely applications

Once soybeans emerge, only a limited number of herbicides can be applied. To keep fields clean as the crop emerges, aim for timely preemergence applications right before the planter goes out and right after it leaves the field. When you fall behind on weed control, you’ve missed an opportunity to achieve your crop’s highest yield potential.

Avoid resprays

With tighter budgets, cutting corners on your preemergence herbicide application might be tempting. However, reducing rates or inconsistent application practices can lead to poor weed control and costly, less effective applications down the road. For best results, use appropriate spray nozzles for the products you’re applying, add the appropriate adjuvants to improve herbicide coverage and wait for favorable environmental conditions before making applications.

With spring planting right around the corner, now is the time to plan your soybean preemergence weed control strategy. Consult your local agronomic advisor or CROPLAN retailer to get started. 

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© 2025 WinField United. Important: Before use always read and follow label instructions. Crop performance is dependent on several factors many of which are beyond the control of WinField United, including without limitation, soil type, pest pressures, agronomic practices and weather conditions. Growers are encouraged to consider data from multiple locations, over multiple years and to be mindful of how such agronomic conditions could impact results. CROPLAN and WinField are trademarks of WinField United.</sub>