Jacksonville
Apply ASAPSoil has cooled to 75°F, so winter weeds are sprouting. Pre-emergent still stops later flushes.
Winter weeds are sprouting now
Live soil temperatures for Jacksonville, Tallahassee, Orlando, Tampa and Miami, updated every three hours. Weeds sprout by soil temperature, not by the calendar, so the right week moves from year to year.
Florida lawns get pre-emergent twice a year: in spring for crabgrass and other summer weeds, and in fall for winter weeds.
Soil is 72–82°F now. They keep coming up in flushes into winter, so pre-emergent still helps. Overseeding this fall? Skip pre-emergent — it stops grass seed too.
Soil 2 inches down, 5-day average: solid line = the last two weeks, dashed = the six-day forecast. Shaded = below 75°F, where winter weeds sprout — pre-emergent has to be down before the line gets there.
Soil has cooled to 75°F, so winter weeds are sprouting. Pre-emergent still stops later flushes.
Winter weeds are sprouting now
Soil has cooled to 75°F, so winter weeds are sprouting. Pre-emergent still stops later flushes.
Winter weeds are sprouting now
Soil already dipped to 75°F, so the first winter weeds are sprouting. Pre-emergent still stops later flushes.
Winter weeds are sprouting now
Soil already dipped to 75°F, so the first winter weeds are sprouting. Pre-emergent still stops later flushes.
Winter weeds are sprouting now
Winter weeds sprout once soil cools to 75°F, and it is 7° above that. Get pre-emergent down before it gets there.
Winter weeds usually start by Nov 3
Spring pre-emergent stops crabgrass. The dates are the University of Florida’s recommendations. Fall pre-emergent stops winter weeds: have it down a week before soil usually cools to 75°F, when they start germinating.
| City | Spring pre-emergent (crabgrass) | Fall pre-emergent (winter weeds) |
|---|---|---|
| Jacksonville | Apply by Mar 1 (UF/IFAS) | Apply by Oct 4 |
| Tallahassee | Apply by Mar 1 (UF/IFAS) | Apply by Sep 24 |
| Orlando | Apply by Feb 15 (UF/IFAS) | Apply by Oct 7 |
| Tampa | Apply by Feb 15 (UF/IFAS) | Apply by Oct 12 |
| Miami | Apply by Feb 1 (UF/IFAS) | Apply by Oct 27 |
These are typical-year dates (the median of 2016–2025); any one year can run a couple of weeks earlier or later, which is what the live readings above are for. For your exact yard, check soil temperature by ZIP.
Granular or liquid. Follow the label rate, and water it in.
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Scotts Halts Crabgrass & Grassy Weed Preventer
Beginner friendly
The Andersons Barricade Professional-Grade Granular
Beginner friendly
Dimension 2EW (Dithiopyr)
Liquid concentrate; 64 oz half gallon; mix with water and spray
The lawn weeds most often identified with our photo identifier in Florida over the last 60 days, as a share of 49 identifications.
Photos: Wikimedia Commons, credited on each weed's page.
The University of Florida recommends having crabgrass pre-emergent down by February 1 in south Florida, February 15 in central Florida and March 1 in north Florida, before daytime highs hold in the upper 60s.
Winter weeds such as annual bluegrass, henbit and chickweed start germinating as soil cools to about 75°F in late summer and fall, and most come up once it is below 70°F. Have fall pre-emergent down before they start: typically by Oct 4 in Jacksonville; by Sep 24 in Tallahassee; by Oct 7 in Orlando; by Oct 12 in Tampa; by Oct 27 in Miami. Skip it if you are overseeding this fall, because it stops grass seed too.
As of Nov 3, 1:18 AM CT: Jacksonville 73°F, Tallahassee 72°F, Orlando 76°F, Tampa 76°F, Miami 82°F (5-day average, about 2.4 inches down). Winter weeds are germinating — apply now if you haven't: Jacksonville, Tallahassee, Orlando and Tampa. Apply fall pre-emergent now: Miami.
How the readings and dates are made, and their limits: Weed Watch method. Soil data: Open-Meteo.com (CC BY 4.0); typical dates: NASA POWER.