A guide released on Apr. 24 provides homeowners with detailed steps to control and prevent crabgrass, a common weed that thrives in dry, compacted soils and areas with damaged turf exposed to sunlight.
Crabgrass can quickly overtake a lawn if left unchecked because each plant is capable of producing thousands of seeds. Effective management is important for maintaining healthy turf and reducing the spread of this invasive weed.
The guide explains that early intervention is crucial since young crabgrass plants are easier to remove than mature ones. The most effective method involves using post-emergent herbicides or manually pulling out the entire root system. While alternatives like horticultural vinegar or boiling water may kill above-ground foliage, they do not destroy the roots, allowing regrowth.
For prevention, applying pre-emergent herbicide in early spring—when soil temperatures reach between 50 and 55 degrees Fahrenheit—is recommended to stop seeds from germinating. Maintaining a dense lawn through proper irrigation, mowing practices, core aeration, dethatching, fertilization based on soil testing, adding soil amendments as needed, and overseeding also helps crowd out crabgrass.
The guide cautions that some selective herbicides may harm certain grass types if misapplied or used during high temperatures. St. Augustinegrass is particularly sensitive to specific chemicals found in these products.
Other organic options such as corn gluten meal are discussed; however, university research has shown mixed results regarding its effectiveness for crabgrass prevention. Additionally, excessive use could contribute to water pollution due to its nitrogen content and may exceed fertilizer regulations in some states.
Homeowners struggling with persistent infestations are advised that full control often takes two seasons: summer removal followed by spring prevention measures over several years. If repeated efforts fail to eliminate the problem entirely, seeking help from professional lawn care services may be beneficial.
