When to Apply Crabgrass Preventer in Illinois

Quick Answer

Apply crabgrass preventer in early spring (typically March–April) before soil temperatures reach 55°F.

Why Timing Is Critical

Crabgrass prevention only works before seeds germinate. Once it’s growing, it’s too late.

Signs It’s Time

• Soil temps near 50–55°F

• Forsythia bushes starting to bloom

• Consistent daytime temps in the 50s

  
  

What Homeowners Should Do

• Apply early, not late

• Avoid seeding at the same time (it blocks grass seed too)

• Follow up with proper fertilization

  
  

Timing this right makes a huge difference. We handle the schedule so you don’t have to think about it.

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