Bayer Advanced 704260A Southern Season Long Weed Control for Lawns Concentrate, 32-Ounces Offers up to 6 months of control with only 1 application Proprietary 2-in-1 formula Post-emergent: kills existing broadleaf weeds Pre-Emergent: Prevents new broadleaf weeds for up to 6 months (Does not provide pre-emergent or post-emergent control of Crabgrass; see product label for kill/prevent weed list) Wont harm lawns (when used as directed)