Orland Park Lawn Care Tips | Preemergent Herbicides
If you know that you have a problem with the annual weeds then fertilization in spring should go hand in hand with the application of preemergent herbicides. Preemergent herbicides address weed control before their seedlings can even emerge. Preemergent herbicides accomplish this by forming a shield that inhibits seed germination.
Crabgrass begins on lawns in spring, when its seeds germinate. My suggestion is that overseeding be carried out in autumn, rather than spring, is based in part on the threat posed by a spring crabgrass invasion. Begin by killing the crabgrass first with a preemergent herbicide in the spring, and overseed in the fall applications works best.