What is the best time to use pre-emergent herbicide for warm season crops?

Using pre-emergent herbicide in spring is optimal for warm season crops because this timing aligns with the growth patterns of many weeds that compete with these crops. Warm season crops, such as corn and soybeans, are typically planted in late spring when soil temperatures rise, promoting vigorous weed emergence. Applying a pre-emergent herbicide in the spring creates a barrier in the soil that inhibits weed seed germination just as conditions become favorable for both the crops and the weeds.

By targeting the spring timeframe, you ensure that the pre-emergent product is in place to thwart weed development at a critical period, ultimately helping to reduce competition for nutrients, water, and sunlight during the vital growth phase of the warm season crops. This approach can lead to healthier crop development and improved yields.