Birmingham
Apply ASAP66°F↓ cooling
Soil has cooled to 75°F, so winter weeds are sprouting. Pre-emergent still stops later flushes.
Winter weeds are sprouting now
Alabama Weed Watch · updated Nov 3, 1:18 AM CT
When to apply pre-emergent in Alabama
Live soil temperatures for Birmingham, Huntsville, Montgomery and Mobile, updated every three hours. Weeds sprout by soil temperature, not by the calendar, so the right week moves from year to year.
Alabama lawns get pre-emergent twice a year: in spring for crabgrass and other summer weeds, and in fall for winter weeds.
Spring pre-emergentNext season
Typically Feb 3 – Mar 9
Stops crabgrass and other summer weeds before they sprout.
Fall pre-emergentThis season
Typically by Sep 3 – Oct 3
Stops winter weeds (annual bluegrass, henbit, chickweed) before they sprout.
Skip it if you are overseeding this fall.
Right now · fall pre-emergent season
Winter weeds are germinating — apply now if you haven't across Alabama
Soil is 63–72°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 temperature by city
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.
Huntsville
Apply ASAP63°F↓ cooling
Soil has cooled to 75°F, so winter weeds are sprouting. Pre-emergent still stops later flushes.
Winter weeds are sprouting now
Montgomery
Apply ASAP67°F→ steady
Soil has cooled to 75°F, so winter weeds are sprouting. Pre-emergent still stops later flushes.
Winter weeds are sprouting now
Mobile
Apply ASAP72°F→ steady
Soil has cooled to 75°F, so winter weeds are sprouting. Pre-emergent still stops later flushes.
Winter weeds are sprouting now
Alabama pre-emergent calendar
Spring pre-emergent stops crabgrass. The window runs from the typical day soil warms to 50°F to the day it holds 55°F, when crabgrass starts germinating (2016–2025). 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) |
|---|---|---|
| Birmingham | Feb 9 – Mar 2 | Apply by Sep 16 |
| Huntsville | Feb 14 – Mar 9 | Apply by Sep 3 |
| Montgomery | Feb 6 – Feb 17 | Apply by Sep 26 |
| Mobile | Feb 3 – Feb 11 | Apply by Oct 3 |
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.
Recommended gear
Fall pre-emergents
Granular or liquid. Follow the label rate, and water it in.
Paid links. As an Amazon Associate, MeasureLawn earns from qualifying purchases.
Amazon
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Scotts Halts Crabgrass & Grassy Weed Preventer
Beginner friendlyPendimethalingranularcovers ~5,000 sq ft / 0.11 ac$24.97as of Nov 2, 10:00 AM UTC · may change
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The Andersons Barricade Professional-Grade Granular
Beginner friendly0.48% Prodiaminegranularcovers ~12,880 sq ft / 0.30 ac$79.88as of Nov 2, 10:00 AM UTC · may change
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Dimension 2EW (Dithiopyr)
Liquid concentrate; 64 oz half gallon; mix with water and spray
Dithiopyrliquidcovers ~91,428 sq ft / 2.1 ac$158.00as of Nov 2, 10:00 AM UTC · may change
What people in Alabama are identifying
We record the state each identification comes from. Alabama's list appears here once it has at least 40 identifications spread over 7 or more days — so no single scan stands out. Until then, see the national list, or add yours:
Identify a weed from a photoWeeds to watch in Alabama this fall
Questions about Alabama
When should I apply crabgrass pre-emergent in Alabama?
Put crabgrass pre-emergent down as soil warms to 50°F, before it holds 55°F and crabgrass starts germinating. In a typical year (2016–2025) that window is Feb 9 – Mar 2 in Birmingham; Feb 14 – Mar 9 in Huntsville; Feb 6 – Feb 17 in Montgomery; Feb 3 – Feb 11 in Mobile.
When should I apply fall pre-emergent in Alabama?
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 Sep 16 in Birmingham; by Sep 3 in Huntsville; by Sep 26 in Montgomery; by Oct 3 in Mobile. Skip it if you are overseeding this fall, because it stops grass seed too.
What is the soil temperature in Alabama right now?
As of Nov 3, 1:18 AM CT: Birmingham 66°F, Huntsville 63°F, Montgomery 67°F, Mobile 72°F (5-day average, about 2.4 inches down). Winter weeds are germinating — apply now if you haven't across Alabama.
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.