Preventing Crabgrass & Goose Grass
Identification
Crabgrass and goose grass are very often incorrectly identified. They are annual plants; that come from seed in early and late-spring. They develop into aggressively spreading plants in June through July. Often people confuse crabgrass and goose grass with other perennial grasses, which are present in lawns year-round. The majority of perennial grasses can not be selectively controlled.
An Ounce of Prevention
Once established, they are very difficult to remove without harming desirable grasses. Get a jump on stopping crabgrass by applying Zamzows Defendz Crabgrass Preventer. This chemical burns up the tender young sprouts of crabgrass. The key to success is timing. If you apply crabgrass preventer too early, the chemical breaks down and allows some late seed to germinate. If applied too late, the stronger young plants will survive the pressure of the herbicide and develop into full-size crabgrass. Mother Nature is the best guide for the timing of the application. When the forsythia bush blooms - the bright yellow flowering shrub pictured above - that tells you that the soil temperatures are warming and you are early enough to apply crabgrass preventer.
You can also prevent goosegrass with an additional application in May. Unfortunately, we don't have an easy visual cue for the timing of this application. Applications should be applied approximately 90 days after an application for crabgrass or in mid-May.
Worth a Pound of Cure
Often soil temperatures vary in yards based on sunny areas versus shade. You need protection over a three month period. In lawns where crabgrass was a severe problem the prior year, it is strongly advised to apply crabgrass preventer twice, 60 to 70 days apart. Once established, there are controls for mature crabgrass, but they are only about 70% effective and require several applications with strict temperature range restrictions for an application.