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Get precise timing recommendations for pre-emergent and post-emergent herbicide applications. Find the optimal windows to control crabgrass, dandelions, and other weeds based on your location and grass type.
Pre-emergent herbicides should be applied before soil temperatures reach 55°F for 3 consecutive days. This is typically in late winter to early spring, depending on your region. In northern areas, this might be March-April, while in southern areas it could be February-March.
Pre-emergent herbicides prevent weed seeds from germinating and should be applied before weeds appear. Post-emergent herbicides kill existing weeds and should be applied when weeds are actively growing. Some products can be used for both purposes depending on timing and application method.
Summer application requires caution. Avoid applying during peak heat (above 85°F) as this can stress your grass and reduce herbicide effectiveness. Apply early morning or evening, ensure adequate soil moisture, and use products specifically labeled for summer application.
Different grass types have varying tolerance to herbicides. Cool-season grasses like Kentucky Bluegrass and Tall Fescue are generally more tolerant, while warm-season grasses may have different requirements. Always check the product label for grass type compatibility before applying.
Broadleaf weeds like dandelions are best controlled in fall (September-October) or early spring (March-April) when they're actively growing but not flowering. Fall application is often most effective because the herbicide is transported to the roots as the plant prepares for winter.