How to Kill Crabgrass in Your Lawn: A Complete Guide

Crabgrass is the bane of many homeowners’ existence. This persistent summer weed can quickly take over a lush green lawn, forming unsightly patches of course grass. But don’t worry – killing crabgrass is possible with the right approach. In this comprehensive guide, we’ll explore the best crabgrass killing methods so you can get rid of it once and for all.

What is Crabgrass?

Crabgrass (Digitaria sanguinalis) is an annual warm season weed that germinates in spring. It thrives in hot, dry conditions. The grassy plant grows low to the ground in circular clumps that can reach two feet in diameter. As the plant matures, it produces branching stems with seed heads that allow it to spread rapidly. When crabgrass dies in autumn, it leaves behind large dead patches in lawns.

While there are several types of crabgrass, the most common is large or hairy crabgrass. This aggressive weed is found throughout the United States and is a headache for homeowners everywhere.

Why Kill Crabgrass?

You may be wondering why it’s so important to kill crabgrass. After all, it’s just a weed right? Wrong. Here are some key reasons you’ll want to get rid of crabgrass pronto:

• It crowds out desirable grass and other plants in your lawn or garden beds

• Crabgrass is unattractive, creating eyesores in an otherwise pristine lawn.

• It hogs water and nutrients that should go to your lawn instead.

• If allowed to go to seed, crabgrass will continue to plague your yard for years to come.

• It creates prime conditions for lawn diseases to take hold by thinning out grass.

• Crabgrass doesn’t match the texture and color of typical lawn grasses It stands out!

As you can see, vigilant crabgrass control is critical for a lush lawn. So let’s get to the good stuff: how to kill it!

Timing is Everything

The first key to success in getting rid of crabgrass is timing your control methods properly. You’ll have the best results if you hit crabgrass at specific points in its lifecycle.

Spring: Apply crabgrass preventer herbicide in early spring before the ground temperature reaches 55°F. This will stop seeds from germinating.

Early Summer: Pull crabgrass as soon as you spot it when plants are young. Or use post-emergent herbicide on newly sprouted crabgrass.

Late Summer: Don’t bother removing mature crabgrass that has set seed. Just let it die out for the year.

Manual Removal

Hand pulling crabgrass is effective for small infestations. Use a garden trowel or crabgrass removal tool to dig out the plants, roots and all. Take care to remove every piece, as any remnants left behind may re-sprout.

Pull only young crabgrass plants. Don’t bother trying to remove large, mature clumps as this can damage your lawn. And never pull crabgrass that has already gone to seed, as this scattering seeds will create more weeds!

It’s best to remove crabgrass after a rain when the soil is slightly moist. Give the lawn a good soaking the day before for easier removal. Plan to re-seed any bare spots left behind to prevent new weeds from invading.

Herbicide Application

For heavy crabgrass infestations, herbicide application is the most effective treatment. Pre-emergent crabgrass killers prevent germination of weed seeds. Post-emergent products kill weeds after they sprout.

Always carefully follow product label instructions when applying any herbicide. Key tips:

• Apply pre-emergent crabgrass preventer in early spring before soil temperatures reach 55°F. This timing is critical.

• Post-emergent herbicides work best on young crabgrass plants under 4 inches tall.

• Avoid herbicide application if rain is expected within 24 hours.

• Use caution around landscape plants, trees and vegetable gardens where herbicide drift may cause damage.

Some common crabgrass killing herbicide ingredients to look for include prodiamine, pendimethalin, and quinclorac. Commercial products like Scotts Halts and Ortho Weed B Gon are also very effective options.

Prevent Future Infestations

Killing crabgrass is only half the battle. You’ll also want to take steps to prevent future weed invasions:

• Maintain a thick, healthy lawn through proper mowing, watering, fertilization and aeration. This crowds out weeds.

• Overseed bare spots in fall with quality grass seed blends.

• Use pre-emergent crabgrass preventer yearly in early spring. This provides season-long control.

• Improve drainage in any wet areas of your lawn that favor crabgrass growth.

• Remove young crabgrass plants promptly whenever you spot them.

• Adjust sprinklers to water lawn deeply, avoiding frequent shallow watering.

Follow these crabgrass killing tips and you’ll be well on your way to a lush, weed-free lawn. Be patient and persistent for best results. With diligent effort and proper timing, you can eradicate crabgrass from your yard for good.

To kill crabgrass without harming your lawn, you can use selective herbicides like Quinclorac or Tenacity. These herbicides are designed to target specific weeds, like crabgrass, while leaving your desired lawn grasses unharmed.