Get Ahead of Winter Weeds With Fall Pre-Emergent

Tuesday, September 22, 2026 | The Greenery, Inc.

As summer comes to an end and temperatures begin to cool down, it’s time to start thinking ahead about your lawn. For homeowners with warm-season turf, fall is an important time to get ahead of winter weeds. A properly timed pre-emergent application can help keep your lawn cleaner in the winter and aid in the reduction of weeds when spring arrives.

Why Apply a Fall Pre-Emergent?

Many winter weeds begin germinating before they are visible above the soil. Pre-emergent herbicides create a barrier in the soil that prevents weed seeds from successfully germinating.

The result is fewer winter weeds and less need for post-emergent herbicides later in the season. Preventing weeds before they appear can also help your lawn transition into spring with better conditions for healthy growth.

Timing Is Key

For warm-season lawns, the ideal fall application window is generally late August through mid-October. However, the application timing isn’t the only factor to consider. Soil temperature can provide an important indication of when winter weeds are preparing to germinate.

Applications should take place before soil temperatures consistently fall below approximately 70°F, when many annual winter weeds begin germinating.

Know Your Turf

Fall pre-emergent applications can be beneficial for established warm-season grasses such as Bermudagrass, Centipedegrass, Zoysiagrass, St. Augustinegrass, and Bahiagrass.

However, pre-emergent isn’t appropriate for every lawn. Newly installed or recently seeded turf may require a different approach. The same is true for areas that will be overseeded with perennial ryegrass. Always consider your lawn’s current condition and future plans before applying a pre-emergent.

Water it into the Soil

Irrigation is an essential part of the pre-emergent application process. Most pre-emergent herbicides need to be watered into the soil to become effective. We recommend approximately ½ inch of irrigation or rainfall within seven days, but each pre-emergent product has different suggestions.

After application, avoid aerating or significantly disturbing the soil, which can disrupt the protective barrier.

You can’t kill weeds that haven’t emerged, but you can prevent them.

A well-timed fall pre-emergent application is a valuable part of a proactive lawn-care program, helping protect established warm-season turf through the winter and setting the stage for a healthier lawn when spring arrives.

Ready to get your lawn prepared for winter? The Greenery, Inc. can help you determine the right approach for your turf and landscape.