TL;DR
Crabgrass preventer is a pre-emergent herbicide, commonly prodiamine, dithiopyr, or pendimethalin, applied to lawns in early spring to form a soil barrier that stops germinating weed seeds before they ever surface. Timing is everything: it goes down before soil temperatures hold near 55°F, the trigger for germination, traditionally pegged to forsythia bloom.
What it means
Crabgrass preventer is a pre-emergent herbicide, commonly prodiamine, dithiopyr, or pendimethalin, applied to lawns in early spring to form a soil barrier that stops germinating weed seeds before they ever surface. Timing is everything: it goes down before soil temperatures hold near 55°F, the trigger for germination, traditionally pegged to forsythia bloom. The same barrier blocks desirable grass seed too, so spring seeding and prevention are mutually exclusive unless the lawn program uses mesotrione or delays one or the other.
Where it sits in the glossary
Crabgrass preventer is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
ProFix Directory keeps definitions short on the index page and saves the longer context — Ohio-specific rules, where the term comes from, and which ProFix tools touch it — for these per-term pages so the term is easy to cite and easy to share.
ProFix tools that touch this term
See also
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