When should I apply pre-emergent herbicide for crabgrass?

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.

What's the difference between pre-emergent and post-emergent herbicides?

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.

How do I know if I'm too late for pre-emergent application?

If you can see crabgrass or other target weeds already growing, you're likely too late for pre-emergent control. However, you can still use post-emergent herbicides to control existing weeds. The key is applying post-emergent products when weeds are young and actively growing.

When is the best time to treat dandelions and broadleaf weeds?

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.

How often should I apply pre-emergent herbicide?

Most pre-emergent herbicides provide 3-6 months of control. For annual weeds like crabgrass, one application in spring is usually sufficient. However, in areas with multiple weed germination periods, a second application in late summer may be needed for weeds that germinate later.