When is the best time to apply the first round of pre-emergent herbicide?

The best time to apply pre-emergent herbicide depends on the type of weeds you are targeting and the climate of your region. Pre-emergent herbicides work by preventing weed seeds from germinating, so timing is crucial for their effectiveness. Here are some general guidelines:

• Soil Temperature: Soil temperature is a critical factor for pre-emergent herbicide effectiveness. You can use a soil thermometer to monitor soil temperatures at a depth of 2 to 4 inches. Apply the herbicide when the soil temperature is in the appropriate range for the target weeds.
• Local Climate Conditions: The timing may vary based on local climate conditions, so it’s essential to monitor weather patterns and soil temperatures in your specific area.
• Apply Before Significant Rainfall or Irrigation: To activate the herbicide, it’s generally recommended to apply it before significant rainfall or irrigation. This helps the product move into the soil where it can create a barrier against weed germination.

Remember that pre-emergent herbicides are most effective when applied before the target weed seeds germinate. Once weeds have emerged, pre-emergent herbicides are not effective, and post-emergent solutions may be necessary. Additionally, it’s crucial to choose a pre-emergent herbicide that is suitable for your specific lawn grass type and that targets the weeds you are trying to control.  At Heartland Turf we customize our program to our Midwest climate and the weeds seen in our region, so call us today to get on the schedule!