Dithiopyr
A pre-emergent herbicide with a unique advantage: it also provides some early post-emergent control of crabgrass in its first leaf stage. This wider application window makes it popular in areas where spring pre-emergent timing is uncertain.
Dithiopyr (sold as Dimension) is unique among pre-emergents because it remains active in the soil longer and can kill very young crabgrass that has just emerged (1–2 leaf stage). This makes it more forgiving if you miss the ideal timing window.
Duration: 3–4 months of soil activity, similar to prodiamine.
Best for: Lawns in climates where spring timing is unpredictable. Transition zone lawns where warm temperatures arrive unevenly.
Grass safety: Safe for most established turfgrasses. Check label for specific grass type clearances.
More on Pre-Emergent
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