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When to plant in River Ridge, LA

USDA Zone 9b

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

A generous ~335-day season lets River Ridge gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. Zone 9b is warm enough that River Ridge can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · NEW ORLEANS INTL AP · 4.8 km
Last spring frost
January 30
50% chance · 32°F
First fall frost
December 31
50% chance · 32°F
Growing season
335 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for River RidgeA year-band showing 32°F frost risk from January to December for River Ridge: last spring frost around January 30, first fall frost around December 31, about 335 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average first fall frost in River Ridge is now 10 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

NEW ORLEANS INTL AP · 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 River Ridge’s own odds, recorded at NEW ORLEANS INTL AP.

Frost-probability curves for River RidgeProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 30 and the first fall frost around December 31, giving about 335 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 12Feb 16Jan 20Nov 16Dec 9Jan 8
32°FFeb 27Jan 30Dec 29Dec 1Dec 31Jan 31
28°FFeb 14Jan 20Dec 24Dec 11Jan 7Feb 6

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 River Ridge, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 19 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.

NEW ORLEANS INTL AP
Primary
5 km · 1 m elevation
SPRING
Jan 30
FALL
Dec 31
NEW ORLEANS AUDUBON
10 km · 6 m elevation
SPRING
Jan 24
FALL
Jan 2
TERRYTOWN 3S
19 km · 3 m elevation
SPRING
Feb 1
FALL
Dec 31

River Ridge planting FAQ

When is the last spring frost in River Ridge, LA?

River Ridge's average last spring frost falls near January 30 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.

When is the first fall frost in River Ridge, LA?

Expect River Ridge's first fall frost near December 31 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.

What hardiness zone is River Ridge in?

River Ridge is in USDA hardiness zone 9b. In zone 9b, winters are mild — many tender perennials overwinter here.

How long is the growing season in River Ridge?

There are roughly 335 frost-free days in River Ridge (a long growing season), running from the average last frost around January 30 to the first fall frost near December 31.

When should I plant tomatoes in River Ridge?

In River Ridge, start tomato seeds indoors around December 5–December 19, then transplant seedlings outdoors around February 6 once the danger of frost has passed.

Planting reminders

Never miss a window in River Ridge

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

Nearby cities

8 within reach

Frost dates recorded at NEW ORLEANS INTL AP, 5 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 River Ridge, LA — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00012916. Retrieved from https://blissgarden.com/louisiana/river-ridge.
When to Plant in River Ridge, LA — Frost Dates & Zone 9b — BlissGarden