Pest of the month: Crabgrass
In the late winter, we talked about the best defense for lawn weeds being pre-emergent weed controls (before the seeds germinate). As we now are heading into late spring, the second-best time to get them under control is while they are still young and juvenile. Crabgrass is the best example of this. If you do not get it under control in spring, you will be having to hand pull it in summer because it will be too developed to control.
Applying a quality pre-emergence herbicide according to label instructions before soil temperatures get too warm is the best way to prevent crabgrass. Of course, having a thick, healthy lawn can win, but it is tough. A properly applied pre-emergence herbicide labeled for crabgrass should prevent the weed from growing throughout the summer. Keep in mind that even the best pre-emergence herbicides will lose their effectiveness later in the summer.
Late in the game?
While it is true that the best way to treat crabgrass is to prevent it, all is not lost. There are post-emergence, selective herbicides labeled for crabgrass, but it gets tricky. Crabgrass is very similar in structure to the desired turf grass in which it grows. Therefore, proper application of these products is very important. Never apply if the temperature is outside the range listed on the label. Applying these products incorrectly may result in damaging your lawn.