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When to plant in Sulphur, LA

USDA Zone 9a

Everything below — frost dates, hardiness zone, and what to plant when in Sulphur, Louisiana — is derived from the closest NOAA station with complete climate normals.

A generous ~296-day season lets Sulphur gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. Sulphur's nearest full-normals station sits about 18 km out, so treat these as a close estimate — local microclimate can nudge your first and last frost. In zone 9a, frost is a minor factor for Sulphur — most perennials thrive, and annual vegetables can go out early and stay late.

Station · LAKE CHARLES · 17.8 km
Last spring frost
February 14
50% chance · 32°F
First fall frost
December 7
50% chance · 32°F
Growing season
296 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for SulphurA year-band showing 32°F frost risk from January to December for Sulphur: last spring frost around February 14, first fall frost around December 7, about 296 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average last spring frost in Sulphur is now 5 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

LAKE CHARLES · 1991–2020

The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Sulphur’s own odds, recorded at LAKE CHARLES.

Frost-probability curves for SulphurProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around February 14 and the first fall frost around December 7, giving about 296 frost-free days.
Last spring frostFirst fall frostbold = 32°F · thin = 28°F / 36°F · dot = 50% date · band = 10–90% window
ThresholdSPRING 10%SPRING 50%SPRING 90%FALL 10%FALL 50%FALL 90%
36°FMar 24Mar 2Feb 8Nov 4Nov 23Dec 13
32°FMar 11Feb 14Jan 16Nov 14Dec 7Jan 7
28°FFeb 28Jan 27Dec 31Dec 3Jan 3Feb 1

Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.

What to plant now

TODAY · JULY 19

Nothing new to sow or transplant outdoors in the next few weeks — a seasonal lull. Check the full-year calendar below for the next window.

Add the next planting windows to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

Each bar is the exact window to take a planting action in Sulphur, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 37 km · complete 32°F normals

When stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.

LAKE CHARLES
Primary
18 km · 4 m elevation
SPRING
Feb 14
FALL
Dec 7
MOSS BLUFF 2 NNW
18 km · 8 m elevation
SPRING
Mar 2
FALL
Nov 25
ORANGE 9 N
37 km · 6 m elevation
SPRING
Feb 28
FALL
Nov 23

Sulphur planting FAQ

When is the last spring frost in Sulphur, LA?

Plan for the last spring frost in Sulphur around February 14 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.

When is the first fall frost in Sulphur, LA?

The first fall frost in Sulphur typically arrives around December 7 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Sulphur in?

Sulphur is in USDA hardiness zone 9a. In zone 9a, winters are mild — many tender perennials overwinter here.

How long is the growing season in Sulphur?

Sulphur has about 296 frost-free days — a long growing season — between the average last spring frost (February 14) and first fall frost (December 7).

When should I plant tomatoes in Sulphur?

For Sulphur, sow tomatoes indoors about December 20–January 3 and move the seedlings out around February 21, after the last spring frost.

Planting reminders

Never miss a window in Sulphur

An email when it’s time to start seeds, transplant, and sow — timed to Sulphur’s frost dates. Double opt-in, one-click unsubscribe, no spam.

Nearby cities

8 within reach

Frost dates recorded at LAKE CHARLES, 18 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.

Cite this page
BlissGarden. "When to Plant in Sulphur, LA — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00003937. Retrieved from https://blissgarden.com/louisiana/sulphur.