When is the best time to treat for crabgrass in the lawn?

Treating for crabgrass is most effective in early spring, prior to the germination of its seeds. Crabgrass is a warm-season annual that thrives during the warmer months, and its seeds typically germinate when soil temperatures reach around 55 to 60 degrees Fahrenheit. By applying pre-emergent herbicides during early spring, before these temperatures are reached, you can effectively inhibit the germination of crabgrass seeds.

Taking action in late fall, during the middle of summer, or in the middle of autumn would not be effective for crabgrass control. In the fall, crabgrass will have already completed its life cycle, meaning treatments would not prevent germination for the following season. Similarly, treating in the middle of summer would miss the critical window for preventing the establishment of new plants, as crabgrass has already likely germinated by then. Lastly, autumn treatments would not address the seeds that lie dormant and wait to sprout in spring, thus failing to prevent the problem in the upcoming growing season. Therefore, early spring is the most opportune time to act, ensuring effective control of crabgrass in the lawn.