Weed
2,4-D pre-emergent
Spring pre-emergent timing
A pre-emergent herbicide forms a chemical barrier in the top inch of soil that stops crabgrass and other summer annual grasses as they germinate. Applied too late, it misses the germination window; applied too early, it breaks down before the seeds activate.
Read the full guide →Shallow soil temperatures are in the action band at 54.3°F at the Durham 2 N sensor, 48 miles from your location.
Window: Apr 1 to May 31. Window typically open for 2 to 3 weeks.
Why this, why now
Safety details (REI, air-temp ceiling, pre-rain)
Keep pets and children off treated areas for 12 hours after application.
Air temperatures above 90°F can volatilize the product or stress the lawn. Wait for cooler conditions.
Apply at least 24 hours before forecast rain so the product binds before runoff.
Reseeding restriction: If you reseeded in the last 16 weeks, do NOT apply.