At some point or another, everyone has had to deal with the unsightly and destructive weed known as crabgrass. A warm season annual, crabgrass reproduces via seeding, and larger crabgrass is generally mat forming and will reproduce via long, rooting tillers. Both types of crabgrass can be found in fertile lawns that are kept moist, but the turf is kept too short or it is thin. Once established, though, crabgrass can grow almost anywhere and is well tolerant to most weather and soil conditions- very aggressively growing, the crabgrass will very easily crowd out the grass that you actually want growing in your lawn. Proper crabgrass removal can go a very long way in preventing crabgrass, but once you have it- there may be some steps that you have to take to make sure that it is gone and stays gone.
The most common method for getting rid of crabgrass is pre-emergent herbicides. Most more common weed and feeds employ this, though many people do not feel that it is concentrated enough to do much good. There are two prominent herbicides in this family: Tupersan and Dimension. Tupersan is one of the better ones because it doesn't impact desirable seed- that is, if you've recently seeded, and you have germinating grass that you do not want to be eliminated, it doesn't harm it. This is usually combined in starter fertilizers in the first place. Dimension is usually also safe, however, this one is notable because it is a long-lasting herbicide- and as crabgrass tends to reseed post weeding, this is an important factor.
When you are working with preemergent herbicides, there are a few things to think about. For instance, you don't want to apply these to new sod, and you should never aerate your lawn directly after using them. You do, however, need to be sure that you reapply and are careful to follow all manufacturer's instructions as needed and that you are careful when you calibrate your spreader for accurate coverage. Also be careful about the type of product you choose because some crabgrass specific herbicides will only take care of the younger crabgrass, not really impacting older, well established plants. If you do choose to hand weed, you should do so well before crabgrass has a chance to seed- otherwise, you're just helping it spread that seed and reproduce much more quickly. Another consideration is, that in regular care and maintains of your yard, if you do keep your grass a little higher than usual- it helps the grass to protect its own turf, making it more difficult for the crabgrass to get the light it needs and in essence, allowing desirable grass to protect itself.
Crabgrass does not have to be a long-term problem. Once removed, careful maintenance of your yard such as making sure that you are only watering occasionally as needed and not slight and daily, as well as proper fertilization and other care can keep crabgrass at bay.