What Is The Best Timing For Weed Control?

The optimum time to control weeds depends on the type and life cycle of the weed and, in some cases, the specific weed and specific herbicide, so the optimum time to control weeds is a complex answer. Regardless of the timing and weed, it is important to select herbicides with a high efficacy for the specific weeds you are targeting.

Spring applications will also control perennial broadleaf weeds, especially if an herbicide is selected that has good activity on the weed and if the correct formulation is chosen.

Winter annual broadleaves can be controlled at the same fall timing as perennial broadleaves. Fall timings are best for winter annuals because they are small after just germinating and herbicides translocate (move inside the plant) well in the fall. Spring control of winter annual broadleaves is more difficult because the weeds are larger and are less likely to translocate herbicide. Additionally, controlling winter annuals in the spring is not typically necessary as these weeds will complete their life cycle and naturally die at the end of the spring.

Summer annual broadleaves and summer annual grasses are best controlled with preemergent herbicides applied in the spring before they germinate. They can also be controlled with post-emergent herbicides in early summer when the temperatures are cooler and before the weeds become too large or produce seed.