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What is Crabgrass?

Crabgrass turns thick, lush, green lawns into thin, weak, patchy lawns. Crabgrass - a troublesome grassy weed - infests lawns across the country. Since there are many different weed grasses, it is critical that the undesirable grass be correctly identified. Identification features are listed below:

Crabgrass establishes from seed every year

Crabgrass is an undesirable grass due to the weakness of the plant's structure,its coarse texture and unsightly color. These characteristics do not blend well into a fine-textured, dark green, Weed Man lawn. Control measures for annual (Crabgrass) and perennial (Dallisgrass) weed grasses differ. Weed Man Knoxville can help determine control methods for both types of grasses.

  • Crabgrass is easy to identify in early spring since only plant skeletons are present at this time.
  • Pre-emergent control applications are the best method to control Crabgrass.  Even with pre-emergent controls applied to the lawn, breakthrough will / can occur with excess heat and drought conditions, excess moisture and weed pressure. 
  • Actively growing Crabgrass cannot be controlled with broadleaf weed control products, only specialty grassy weed control product.
  • Crabgrass  favors bare or thin turfgrass areas within the lawn. A strong, healthy, properly fertilized, mowed and watered Weed Man lawn provides the strongest defense against crabgrass. Thick, lush, insect and weed free lawns allow few open sites for crabgrass to establish.

Remember, crabgrass grows from seed every year in weakened, stressed areas!


A thick healthy lawn is the best Crabgrass control but that alone is not 100%.  Weed Man Knoxville applies special pre emergent crabgrass control material in winter or very early spring before the crabgrass seeds germinate. This process continues through the spring. This material will form a barrier to stop crabgrass seed roots as they germinate. Following application, this barrier must not be broken by raking or digging.

Crabgrass will establish in the unprotected areas. Your Weed Man can strengthen your lawn by applying his specially formulated fertilizer program. He can beautify your lawn with weed control, insect control - if necessary - and advise you on proper mowing and watering procedures. Crabgrass in the lawn can be reduced over a few seasons of special care by your Weed Man and yourself. A thick, dark green, crabgrass-free lawn is well worth the patience and special care.