Why do I have crabgrass this year, even though crabgrass preventer was applied?
We had very warm temperatures that started in April and lasted into late September. Along with the hot, sunny days. The Crabgrass preventer must be watered into the lawn before the forsythia blooms and must have consistent amount of moisture to remain effective, if your lawn dried out because of drought or sprinkler problems, then starts getting frequent rainfall or watering, with warm temperatures you may get crabgrass seed germination. Sun light and heat can also shorten the preventers life in the soil, just as the sun makes things fad, we had day after day with 100% sunshine reducing the preventers longevity. One draw back of crabgrass preventer, is that you cannot reseed the lawn with the preventer in the soil, if reseeding is done and you raked the surface, you have just destroyed the preventive barrier in those areas.
What is Crabgrass
Crabgrass is a annual weed in the grass family that only grows from seeds. It starts out in the spring looking like any normal blade of grass in the lawn but gets its name because by July it begins to send out crab like runners that grow in all directions. Crabgrass loves the sun and hot weather so as summer heat gets going the faster it grows. Crabgrass will not grow in dense shade
How to keep crabgrass out of the lawn
The best way to control crabgrass is to have a thick, healthy turf and keeping your lawn watered evenly. Unfortunately things like; squirrels digging or kids playing can damage turf letting sunlight in, so that crabgrass can germinate. This is why we put done crabgrass preventers. By applying crabgrass preventers in early spring before the seeds start to germinate. Crabgrass preventers are usually in granular form and work by being slowly dissolved by water to form a barrier that is 1/8" to 1/4" thick, that actually prevents most annual plant seeds beneath this barrier from germinating. The preventers that we use usually stay active in the soil from 8 to 12 weeks.