Pre-Emergent Weed Control Timeline for DFW: When to Apply for Crabgrass Prevention

Pre-emergent herbicide applied before soil temperatures reach 65°F prevents 90% of summer crabgrass and annual weed invasions. In DFW, this critical timing falls between February 15 and March 15—miss this window and face an entire season of weed battles.

The Science of Pre-Emergent Timing

Pre-emergent herbicides create a soil barrier that prevents weed seed germination—they don't kill existing weeds.

Annual weeds like crabgrass germinate when soil temperatures consistently reach 55-60°F at 2-inch depth. Once germination occurs, pre-emergent is ineffective. This creates a narrow application window before spring warming triggers weed growth.

DFW Pre-Emergent Application Calendar

Primary Application: February 15 - March 15

Target conditions:

• Soil temperature approaching 55°F sustained
• Before consistent 65°F days
• After last hard freeze risk (typically mid-February)

Application rate: Product-specific, typically 3-4 lbs per 1,000 sq ft for granular formulations

Secondary Application: May 1 - June 1

Extended season products benefit from split application:

• Reinforces barrier as primary application degrades
• Targets late-germinating weed seeds
• Extends control through peak summer heat

Fall Pre-Emergent: September 1-15

Winter annual weed prevention (Poa annua, henbit, chickweed):

• Prevents winter weed establishment
• Different chemistry than spring application
• Less critical than spring timing but beneficial

Recommended Pre-Emergent Products

Dimension (Dithiopyr)

Advantages:

• Extended control (3-4 months)
• Early post-emergent activity on young crabgrass
• Suitable for Bermuda, St. Augustine, Zoysia

Application: February-March primary, optional May follow-up

Barricade (Prodiamine)

Advantages:

• Longest residual (4-6 months)
• Excellent crabgrass prevention
• Lower cost than Dimension

Application: Single February-March application often sufficient

Pendulum (Pendimethalin)

Advantages:

• Broad-spectrum weed control
• Established track record

Limitations: Shorter residual, may require split application

Application Best Practices

Site Preparation

• Mow lawn to normal height before application
• Remove existing weeds (pre-emergent won't kill established weeds)
• Ensure soil is not saturated (moderate moisture ideal)

Application Technique

• Even distribution using calibrated spreader
• Two-directional passes for uniform coverage
• Edge and border attention
• Follow immediately with 0.5 inch irrigation to activate

Post-Application Care

• Delay mowing 24-48 hours
• Aeration should precede application, not follow immediately
• Continue regular irrigation to maintain barrier

Common Mistakes to Avoid

• Late application: Once crabgrass germinates, pre-emergent is ineffective
• Under-application: Insufficient rate creates gaps in barrier
• Failure to water in: Product must reach soil to create barrier
• Expecting miracles: Pre-emergent prevents seeds, doesn't kill established weeds

DIY vs. Professional Application

DIY: Product available at garden centers ($40-$80 per 5,000 sq ft), requires proper spreader calibration and timing awareness

Professional: Sandoval Landscaping pre-emergent service includes:

• Optimal timing notification and application
• Professional-grade products with extended control
• Proper application equipment and technique
• Integrated with fertilization program
• Follow-up monitoring

Conclusion

Pre-emergent timing is everything—one properly timed application prevents an entire season of crabgrass battles. Sandoval Landscaping's lawn care programs include precisely timed pre-emergent applications for DFW's specific climate patterns.

Learn more about lawn care: Smart Irrigation & Water Management Guide