Crabgrass is Nashville's worst summer weed, and you can't spray it away once it's up — you have to prevent it. Put down a pre-emergent in late February to mid-March, before soil temperatures hit about 55°F (the local rule of thumb: when the forsythia blooms).
Miss that window and crabgrass germinates and takes over by July. Watch the soil temperature — it's the trigger, not the calendar. Here's where central Nashville's soil is right now:
Apply in early March (soil under 55°F) to stop crabgrass and poa annua before they germinate.
Scotts Halts Crabgrass & Grassy Weed Preventer
Beginner friendlyThe Andersons Barricade Professional-Grade Granular
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Not sure what you've got? Identify it from a photo or browse the weed guide for the exact treatment.
Sedge is its own category — these target nutsedge specifically.
SedgeHammer Plus Turf Herbicide (13.5g)
Beginner friendlyYellow and purple nutsedge, kyllinga, horsetail — the go-to sedge herbicide for homeowners
Image Kills Nutsedge Concentrate (24 oz)
Beginner friendlyNutsedge and dollarweed on warm-season lawns — attacks tubers underground for lasting control
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Herbicides treat the symptom; a dense lawn fixes the cause. Weeds move into thin, bare, compacted turf. The single best thing you can do is keep Nashville fescue thick: aerate and overseed every fall, mow high (3.5–4″), and fertilize on the right schedule. A full canopy crowds weeds out before they start.
Late February to mid-March, before soil temperatures reach about 55°F — typically the first or second week of March in Middle Tennessee, or "when the forsythia blooms." Applying after crabgrass has sprouted is too late. Apply a second pre-emergent in late summer/early fall for poa annua.
Use a sedge-specific herbicide (with halosulfuron or sulfentrazone). Nutsedge is not a true grass or broadleaf, so regular weed-and-feed and most lawn weed killers won't control it. It thrives in Nashville's wet clay in summer, so improving drainage helps too.
There isn't one — it depends on the weed. Use a pre-emergent for crabgrass and poa annua, a broadleaf post-emergent for dandelion and clover, triclopyr for wild violet and ground ivy, and a sedge-specific product for nutsedge. Matching the chemistry to the weed is what works.
Fall is the most effective time to spray broadleaf weeds like dandelion and clover, because they're moving energy down to their roots and carry the herbicide with it. Spring works too, but fall gives the longest-lasting control. Spray on a calm, mild day.
Weed-and-feed can knock back broadleaf weeds, but it has two problems here: the timing rarely matches both the feeding window and the weed window, and it does nothing for nutsedge or crabgrass (which needs a pre-emergent). Targeted products applied at the right time work far better.
Herbicides are dosed per 1,000 sq ft — measure your Nashville lawn free in ~2 minutes so you buy the right amount and don't over- or under-apply.
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