Despite proper cultural practices, crabgrass may still remain problematic in certain turf areas. The best approach to controlling crabgrass is to use a preemergence herbicide such as dithiopyr (Dimension), pendimethalin (Pendulum), prodiamine (Barricade), prodiamine + quinclorac (Cavalcade PQ), sulfentrazone + prodiamine (Echelon), and others. These herbicides inhibit cell division and prevent crabgrass seeds from properly emerging. Since these herbicides work on germinating seeds, you must apply them before germination — with the exception of dithiopyr, which controls crabgrass after germination until it reaches one tiller.

When to apply preemergence herbicide for crabgrass control?

Despite proper cultural practices, crabgrass may still remain problematic in certain turf areas. The best approach to controlling crabgrass is to use a preemergence herbicide such as dithiopyr (Dimension), pendimethalin (Pendulum), prodiamine (Barricade), prodiamine + quinclorac (Cavalcade PQ), sulfentrazone + prodiamine (Echelon), and others. These herbicides inhibit cell division and prevent crabgrass seeds from properly emerging. Since these herbicides work on germinating seeds, you must apply them before germination — with the exception of dithiopyr, which controls crabgrass after germination until it reaches one tiller.


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