Warmer, drier weather will create a window of opportunity to apply crabgrass preventer
Hopefully, now that the ice and snow have melted and spring weather is rapidly approaching, it’s time to apply early season crabgrass preventer. Crabgrass is a summer annual grass that will reestablish itself each year from seed that remains near the soil surface from last year’s crabgrass crop. The seed of crabgrass begins to germinate in areas of a lawn where light can penetrate to the soil surface and the soil temperatures warm to nighttime minimum temperatures of 52 – 54 F for at least 5 consecutive nights under conditions of moist soils.
When applied in a timely fashion, preemergence herbicides can effectively control the germination of crabgrass. A “timely” application requires that the herbicide be applied and rained into the soils surface before soil temperatures are such that germination can occur. In Fairfield County, ideal timing for the application of a crabgrass preventer herbicide is typically early April, although with this year’s late arriving spring has delayed the ideal time until at least mid-April.
Homeowners are able to purchase crabgrass preventers or crabgrass killers and apply them to their lawn if they wish. You can find list of examples of pre-emergence herbicides available to prevent crabgrass germination on the Fairfield County OSU Extension website under the County News section. Corn gluten meal is a popular natural fertilizer that also has substances in it that are reported to inhibit crabgrass and other weed seed germination.
Once crabgrass germinates and emerges, although somewhat less effective than “preventers” there are a few postemergence products available to suppress or eliminate it from lawns.