• Healthy lawns resist weeds.grass image by green308 from Fotolia.com
  
  Crabgrass is a common summer weed that typically germinates in soil temperatures of 60 degrees F or more. It normally flowers and sets seed during early summer. The weed has a high survival and reproductive capacity, and a lawn without its presence is rare. However, cultural and chemical methods exist to get rid of crabgrass.
  
  

Mowing

• Control crabgrass with strategic mowing. Set the lawn mower to cut as high as possible; ideally, 2 to 3 inches is enough to eliminate crabgrass. Mowing anywhere below this range will only help increase the growth of crabgrass. Crabgrass cannot germinate in the shade, so keeping the grass a little longer will ensure the creation of a non-optimal environment. Mow frequently, as this will help the turf and inhibit crabgrass from getting healthier. Mow enough so as not to remove over 1/3 of the leaf blades during the mowing. This amounts to twice weekly mowing in spring and every other week during summer.
  
  

Watering

• Water the lawn infrequently but deeply. A light, daily watering promotes shallow, non-drought hardy lawns and encourages the growth of crabgrass. When watering, the soil should be wet all the way to the grass roots. Refrain from watering until you see initial signs of drought stress, indicated by a bluish-gray shade in the turf and signs of footprints when walked on. When the lawn is allowed to dry in this manner, the germination of shallow-rooted crabgrass is inhibited. Deep watering also helps the lawn grass to develop deeper root systems with a greater resilience to survive in less-than-optimal conditions. Healthy grass is also able to evade weeds more aggressively.
  
  

Overseeding

• Overseeding the lawn is a natural way to discourage the growth of crabgrass. By filling in all the open and less inhabited areas on the lawn ground, you reduce the possibility for crabgrass to find footing to grow. The best time to reseed or overseed is during early fall since grass germinates faster in warm soil. After the first frost, there will be less chances of it having to compete with crabgrass, since crabgrass likes warm soil to grow. Even though overseeding involves a lot of work such as raking, mowing and watering, it is only required once every five years. At that pace, there is little chance of facing problems with crabgrass in the long run.