How to Win the Fight Against Crabgrass

Brian McMaster

Regardless of what part of the country your lawn is in, chances are you’ve either experienced crabgrass taking over your lawn or are aware of it.  Most will agree it’s one of the biggest nuisance weeds that can tarnish an otherwise beautiful lawn.  

Crabgrass is a grassy weed and can appear very similar to other grassy weeds and even the grass in your lawn itself.  Many people just call any weed that looks like grass crabgrass. In fact, I've even heard multiple people from up north say that the lush St. Augustine lawns of the south are “what we used to call crabgrass back home.”



How Difficult is it to Get rid of Crabgrass?

Completely eradicating crabgrass from your lawn can prove to be a difficult task and varies depending on the primary turf type of your lawn.  For all lawn types, preventing crabgrass is however much easier than removing existing crabgrass from your lawn.  For this reason it is essential to start your battle against crabgrass with a preventative application of pre-emergent herbicide.
  

Killing existing crabgrass from your lawn is possible, but depending on what type of turf grass is in your lawn can affect how difficult it is to safely apply a post-emergent herbicide that will kill existing crabgrass without harming your desirable lawn grass.



How Long Does it Take to Get Rid of Crabgrass?

If you are expecting immediate results when attempting to eradicate crabgrass from your lawn, then maybe lawn care isn’t a good choice for you.  It’s typically going to take at least a growing season to get ahead of the crabgrass fight.  Depending on how big your existing crabgrass problem is will determine how long it takes to get rid of. Also, remember that if you have crabgrass this year, it’s going to come back next year! 


When treating small or individual patches of existing crabgrass with a post-emergent herbicide, you can expect to see visible results within a few weeks.  With effective post-emergent herbicide applications, these small patches of crabgrass will wither and die to leave your lawn to fill the void.


However, larger clumps of crabgrass that have begun to overtake your lawn indicate an older and mature stand of crabgrass that is going to take even longer to control.  These bigger patches of crabgrass will have begun a process called “tillering” which means they are growing into bigger clumps of crabgrass from underground roots.  This stage of crabgrass is much stronger and may require several treatments throughout one growing season to get under control.


Additionally, once the crabgrass has been killed, you may be left with large bare areas that may need either sodded or seeded to re-establish your lawn turf in those areas.




How Do You Actually Get Rid of Crabgrass?

Since grassy weeds like crabgrass are very similar to the desirable turf grass that we want in our lawns, it is going to be a difficult task to get rid of crabgrass from your lawn. This is why it is essential to properly identify what type of crabgrass or other grassy weed is actually growing in your lawn so that efforts are not wasted. 


These are the basic steps to get rid of crabgrass in your lawn:

  1. Identify the weed

  2. Prevent future weeds

  3. Remove existing weeds

  4. Maintain control


Step One: Identify the weed

it is important to have properly identified your grassy weed and verified what you are trying to eliminate from your lawn.  Some grassy weeds that can be misidentified as crabgrass are in fact even harder to get rid of compared to true crabgrass.  Grassy weeds such as Common Bermudagrass, and Torpedograss can not effectively be prevented with pre-emergent herbicides.


Oftentimes many other grassy weeds are misdiagnosed and broadly generalized as crabgrass. 


Grassy weeds similar to crabgrass
  • Torpedograss

  • Bermudagrass

  • Alexandergrass or Signalgrass

  • Goosegrass

  • Doveweed

  • Sedges

There are actually five different varieties of crabgrass that grow in Florida

  • India crabgrass

  • blanket crabgrass

  • southern crabgrass

  • tropical crabgrass

  • smooth crabgrass


Step Two: Prevent future weeds

The first step in preventing any weeds, especially grassy weeds such as crabgrass, is having a healthy, thick lawn that can naturally out-compete weeds.  Additionally, a pre-emergent herbicide can be applied that will stop the weeds from growing as they sprout from their seeds.  The timing of these pre-emergent applications needs to coincide with the season in which the weed starts to grow from seeds. Crabgrass is an annual grassy weed and the best time to prevent it is in the late winter or early spring.


Step Three: Remove existing weeds

If you already have crabgrass in your lawn, there are certain products available to kill the crabgrass in your lawn. Extra care should be taken when applying these products as they can be harmful to the desirable grass in your lawn. One should typically consult a lawn care professional for help with these applications.


Bare spots may develop and renovation may be needed for large areas overrun with crabgrass.  It’s also worth noting that annual grassy weeds such as crabgrass will naturally die each winter in the cold weather.  With the exception of some areas in Florida where the weather just doesn’t get cold enough, crabgrass may persist into next season.


Step Four: Maintain Control

Battling crabgrass is not a one and done process. It takes a holistic approach every season to ensure you can reduce existing crabgrass populations and prevent future outbreaks.  Proper cultural practices such as correct mowing height and correct irrigation are important contributing factors to a healthy lawn.


Additionally, fertilize as recommended for your lawn type and be sure to be on a good preventative weed control program if you want to maintain control and keep crabgrass out of your lawn for good!


Consider Hiring a Professional

Fortunately for you, our annual lawn care programs offer year round protection from crabgrass.  Seasonal applications of pre-emergent herbicides prevent new seeds from sprouting.


We also encourage a strong healthy lawn with multiple granular and liquid fertilizer applications throughout the season. 


If you would like a free consultation on your lawn’s health or crabgrass problem, please do not hesitate to inquire about our lawn care programs today!