To win the war against crabgrass, combine professional care with good follow-up practices. Thousands of seeds produced by last year’s crabgrass plants were blown and carried virtually everywhere. The trick is to keep the seeds from germinating. For that, action has to be taken early in the season, before weather gets too warm. Once seeds have germinated, aggressive crabgrass plants can take over. Professional treatment includes an application of a preemergence herbicide, watered in by rainfall or supplemental sprinkling, creating a barrier against sprouting crabgrass.
Keep this barrier intact by not raking and by watering to keep the soil from drying out and cracking. Postpone core aeration until later in the season.
You should also be sure not to cut your lawn too short. Such “scalping” leads to grass thinning, making it easier for crabgrass to flourish. For the same reason, don’t get too aggressive with your string trimmer or blade edger.
In some seasons and areas, a second application may be a good idea. If some crabgrass plants get growing even under your watchful eye, post emergence controls are available to take care of them.
Healthy, dense turf chokes out crabgrass, so the best defense against these unwanted plants is to combine our treatments with good mowing and watering practices to promote vigorous growth.