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When to plant in Slidell, LA

USDA Zone 9a

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

A generous ~280-day season lets Slidell gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. In zone 9a, frost is a minor factor for Slidell — most perennials thrive, and annual vegetables can go out early and stay late.

Station · SLIDELL · 2.9 km
Last spring frost
February 24
50% chance · 32°F
First fall frost
December 1
50% chance · 32°F
Growing season
280 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for SlidellA year-band showing 32°F frost risk from January to December for Slidell: last spring frost around February 24, first fall frost around December 1, about 280 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

SLIDELL · 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 Slidell’s own odds, recorded at SLIDELL.

Frost-probability curves for SlidellProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around February 24 and the first fall frost around December 1, giving about 280 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°FApr 2Mar 12Feb 18Nov 1Nov 16Dec 7
32°FMar 19Feb 24Jan 29Nov 9Dec 1Jan 3
28°FMar 6Feb 4Jan 4Nov 26Dec 26Jan 26

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

What to plant now

TODAY · JULY 19
Fall sowin 23 days
Brussels Sprouts
August 11August 25

Add these crops to your calendar (.ics) ↓

Full-year planting calendar

Start indoorsTransplantDirect sowFall sow

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

Nearby weather stations

3 within 20 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.

SLIDELL
Primary
3 km · 3 m elevation
SPRING
Feb 24
FALL
Dec 1
SLIDELL AP
7 km · 8 m elevation
SPRING
Mar 3
FALL
Nov 21
BAY ST LOUIS NASA
20 km · 9 m elevation
SPRING
Mar 6
FALL
Nov 19

Slidell planting FAQ

When is the last spring frost in Slidell, LA?

On average, the last spring frost in Slidell is around February 24 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.

When is the first fall frost in Slidell, LA?

Expect Slidell's first fall frost near December 1 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is Slidell in?

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

How long is the growing season in Slidell?

Slidell has about 280 frost-free days — a long growing season — between the average last spring frost (February 24) and first fall frost (December 1).

When should I plant tomatoes in Slidell?

For Slidell, sow tomatoes indoors about December 30–January 13 and move the seedlings out around March 3, after the last spring frost.

Planting reminders

Never miss a window in Slidell

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

Nearby cities

8 within reach

Frost dates recorded at SLIDELL, 3 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 Slidell, LA — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00168539. Retrieved from https://blissgarden.com/louisiana/slidell.