Crabgrass is a warm-season annual that germinates, lives and dies all in the same year. While they live, each crabgrass plant produces up to 150,000 seeds. With hundreds of thousands of crabgrass seeds potentially waiting in your lawn, preventing their successful germination is essential.
A well timed application of pre-emergent and a good nutrient rich fertilizer will help stop that germination and invasion. Pre-emergents work by inhibiting seed germination and root development so that seeds can’t become established plants.
Because crabgrass preventers only work before crabgrass seedlings emerge through the soil, timing applications right is critical to success. Crabgrass starts germinating when soil temperatures warm to 55 degrees Fahrenheit for four to five days in a row. A few or more warm days will not be a factor as the soil temperature takes a little longer to rise.
If your lawn hasn’t been treated in the past, it could take 1-3 years to fully control crabgrass.