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When to plant in La Porte, TX

USDA Zone 9b

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

A generous ~317-day season lets La Porte gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. These dates come from a station roughly 22 km away, the closest with full normals; terrain around La Porte (elevation, water, pavement) can move your real frost dates a few days either way. Zone 9b is warm enough that La Porte can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · HOUSTON NWSO · 22.0 km
Last spring frost
January 31
50% chance · 32°F
First fall frost
December 14
50% chance · 32°F
Growing season
317 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for La PorteA year-band showing 32°F frost risk from January to December for La Porte: last spring frost around January 31, first fall frost around December 14, about 317 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

The average last spring frost in La Porte is now 12 days earlier than in the 1981–2010 normals. See how frost dates are shifting nationwide →

Frost probability

HOUSTON NWSO · 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 La Porte’s own odds, recorded at HOUSTON NWSO.

Frost-probability curves for La PorteProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around January 31 and the first fall frost around December 14, giving about 317 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 17Feb 22Jan 21Nov 9Nov 29Dec 22
32°FMar 5Jan 31Dec 25Nov 19Dec 14Jan 19
28°FFeb 24Jan 17Dec 19Dec 6Jan 3Feb 5

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 La Porte, drawn to the day from the local frost dates. The dashed line is today.

Nearby weather stations

3 within 24 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.

HOUSTON NWSO
Primary
22 km · 6 m elevation
SPRING
Jan 31
FALL
Dec 14
HOUSTON HOBBY AP
23 km · 13 m elevation
SPRING
Jan 30
FALL
Dec 28
HOUSTON-PORT
24 km · 6 m elevation
SPRING
Feb 2
FALL
Dec 25

La Porte planting FAQ

When is the last spring frost in La Porte, TX?

Plan for the last spring frost in La Porte around January 31 (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 La Porte, TX?

In La Porte, the first 32°F freeze of fall lands around December 14 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is La Porte in?

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

How long is the growing season in La Porte?

There are roughly 317 frost-free days in La Porte (a long growing season), running from the average last frost around January 31 to the first fall frost near December 14.

When should I plant tomatoes in La Porte?

In La Porte, start tomato seeds indoors around December 6–December 20, then transplant seedlings outdoors around February 7 once the danger of frost has passed.

Planting reminders

Never miss a window in La Porte

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

Nearby cities

8 within reach

Frost dates recorded at HOUSTON NWSO, 22 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 La Porte, TX — Frost Dates & Zone 9b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00414333. Retrieved from https://blissgarden.com/texas/la-porte.