Pre-emergent crabgrass killer: When to apply this season
I live in Rockville and we have had a lot of crabgrass the past year. Given that we have not had a winter, when should be apply pre-emergent crabgrass killer? I don't have a soil thermometer so the recommendations about soil temp are no help to me! Thanks.
The timing for the crabgrass pre-emergent application can be figured by watching the early spring, yellow-blooming forsythia shrub. (way easier than knowing the soil temps.
Essentially any time now will be o.k. If we go back to 'normal' cold temps and stay there, a second application in early to mid-April can be helpful.
Try to find a product that is not "weed and feed" (the best time to fertilize is in the fall). You are looking for the active ingredient (small print) pendimethalin or prodiamine.