How to Kill Crabgrass in Indianapolis the Right Way

If you see a low, sprawling weed with wide blades taking over your lawn each summer, you have met crabgrass. This annual weed loves our hot Indianapolis summers and thrives in thin, weak lawns. Once it appears, it spreads aggressively, smothering your good grass. Learning how to kill crabgrass effectively requires a two-part strategy: eliminating what you see now and preventing it from coming back next year.

Crabgrass seeds germinate in spring, grow all summer, spread thousands of new seeds, and die at the first frost. This cycle means a single plant can plague your yard for years. Simply pulling it often leaves seeds behind. The right approach tackles both the immediate plant and the future problem.

Step 1: How to Kill Crabgrass that already exists

For crabgrass that has already sprouted, you need a post-emergent herbicide. Look for products labeled specifically for crabgrass in lawns. These are often “selective” herbicides, meaning they target the weed without killing your turfgrass. For best results:

• Apply on a calm, sunny day when the crabgrass is actively growing.

• Ensure the product is safe for your specific grass type (Kentucky bluegrass, fescue, etc.).

• Spot-treating individual patches is often more effective and safer for your lawn than a blanket application.

Important note: Mature crabgrass is very tough to kill. The most effective time for post-emergent control is when the plants are young and small, typically in late spring to early summer.

Step 2: Prevent Future Crabgrass with Pre-Emergent

This is the most critical step for long-term control. A pre-emergent herbicide creates a barrier at the soil surface that stops crabgrass seeds from sprouting.

• Timing is Everything: In Indianapolis, apply pre-emergent in early to mid-spring, when soil temperatures consistently reach 55-60°F. A good indicator is when forsythia bushes are in full bloom.

• Application is Key: The barrier must be watered in lightly after application to activate it. It must also be undisturbed; core aeration or heavy raking after application will break the barrier.

Step 3: How to Build a Lawn That Resists Crabgrass

Crabgrass needs sunlight and space. A thick, healthy lawn is the best natural defense.

• Mow High: Keep your grass at 3 inches or taller. This shades the soil, preventing crabgrass seeds from getting the light they need to germinate.

• Fertilize Properly: Feed your lawn in spring and fall to promote dense growth that crowds out weeds.

• Overseed Bare Spots: Fill in thin areas in the fall with quality grass seed. Bare soil is an open invitation for crabgrass.

How to Kill Crabgrass the Right Way

Knowing how to kill crabgrass involves precise timing and the right products. For homeowners in Fishers, Carmel, and Greenwood, this can be a complex and time-sensitive task.

Let Blue Duck Lawn Care handle it. Our weed control program applies pre-emergent at the perfect moment in spring and manages any breakthroughs with targeted treatments. We combine this with fertilization and overseeding to build a thick lawn that naturally resists crabgrass and other weeds.

Don’t let crabgrass win another summer. Contact Blue Duck Lawn Care today for a free lawn evaluation and let us show you the professional way how to kill crabgrass for good.