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When to plant in Portland, TX

USDA Zone 10a

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

A generous ~325-day season lets Portland gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. These dates come from a station roughly 21 km away, the closest with full normals; terrain around Portland (elevation, water, pavement) can move your real frost dates a few days either way. In zone 10a, frost is a minor factor for Portland — most perennials thrive, and annual vegetables can go out early and stay late.

Station · CORPUS CHRISTI NWS · 21.0 km
Last spring frost
January 31
50% chance · 32°F
First fall frost
December 22
50% chance · 32°F
Growing season
325 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for PortlandA year-band showing 32°F frost risk from January to December for Portland: last spring frost around January 31, first fall frost around December 22, about 325 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

CORPUS CHRISTI NWS · 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 Portland’s own odds, recorded at CORPUS CHRISTI NWS.

Frost-probability curves for PortlandProbability 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 22, giving about 325 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 18Jan 18Nov 16Dec 7Jan 4
32°FMar 2Jan 31Dec 24Nov 29Dec 22Feb 1
28°FFeb 17Jan 11Dec 13Dec 7Jan 1Feb 4

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

Nearby weather stations

3 within 23 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.

CORPUS CHRISTI NWS
Primary
21 km · 13 m elevation
SPRING
Jan 31
FALL
Dec 22
CORPUS CHRISTI
21 km · 14 m elevation
SPRING
Jan 28
FALL
Dec 21
CORPUS CHRISTI CABANISS FLD
23 km · 9 m elevation
SPRING
Jan 15
FALL
Dec 30

Portland planting FAQ

When is the last spring frost in Portland, TX?

Plan for the last spring frost in Portland 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 Portland, TX?

In Portland, the first 32°F freeze of fall lands around December 22 on average. Time your last harvests and any season-extension cover before it.

What hardiness zone is Portland in?

Portland is in USDA hardiness zone 10a. In zone 10a, winters are mild — many tender perennials overwinter here.

How long is the growing season in Portland?

Portland has about 325 frost-free days — a long growing season — between the average last spring frost (January 31) and first fall frost (December 22).

When should I plant tomatoes in Portland?

For Portland, sow tomatoes indoors about December 6–December 20 and move the seedlings out around February 7, after the last spring frost.

Planting reminders

Never miss a window in Portland

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

Nearby cities

8 within reach

Frost dates recorded at CORPUS CHRISTI NWS, 21 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 Portland, TX — Frost Dates & Zone 10a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00412011. Retrieved from https://blissgarden.com/texas/portland.