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When to plant in Rosenberg, TX

USDA Zone 9a

Rosenberg, Texas frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.

Rosenberg enjoys a long ~307-day frost-free season — you can succession-sow, fit in a second crop, and grow long-season heat-lovers with room to spare. Rosenberg'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. Zone 9a is warm enough that Rosenberg can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.

Station · SUGAR LAND · 17.8 km
Last spring frost
February 9
50% chance · 32°F
First fall frost
December 13
50% chance · 32°F
Growing season
307 days
frost-free
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Frost calendar for RosenbergA year-band showing 32°F frost risk from January to December for Rosenberg: last spring frost around February 9, first fall frost around December 13, about 307 frost-free days between.
Shaded months carry frost risk; the clear span is the average frost-free season.

Frost probability

SUGAR LAND · 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 Rosenberg’s own odds, recorded at SUGAR LAND.

Frost-probability curves for RosenbergProbability of the last spring frost and first fall frost by date at 32°F. The last spring frost is most likely around February 9 and the first fall frost around December 13, giving about 307 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 25Mar 2Feb 2Nov 9Nov 29Dec 20
32°FMar 11Feb 9Jan 13Nov 19Dec 13Jan 13
28°FFeb 28Jan 28Dec 26Nov 30Jan 1Feb 2

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 Rosenberg, 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.

SUGAR LAND
Primary
18 km · 26 m elevation
SPRING
Feb 9
FALL
Dec 13
HOUSTON SUGARLAND MEM
18 km · 25 m elevation
SPRING
Feb 2
FALL
Dec 11
THOMPSONS 3 WSW
20 km · 21 m elevation
SPRING
Feb 15
FALL
Dec 6

Rosenberg planting FAQ

When is the last spring frost in Rosenberg, TX?

Rosenberg's average last spring frost falls near February 9 — 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 Rosenberg, TX?

The first fall frost in Rosenberg typically arrives around December 13 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.

What hardiness zone is Rosenberg in?

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

How long is the growing season in Rosenberg?

There are roughly 307 frost-free days in Rosenberg (a long growing season), running from the average last frost around February 9 to the first fall frost near December 13.

When should I plant tomatoes in Rosenberg?

In Rosenberg, start tomato seeds indoors around December 15–December 29, then transplant seedlings outdoors around February 16 once the danger of frost has passed.

Planting reminders

Never miss a window in Rosenberg

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

Nearby cities

8 within reach

Frost dates recorded at SUGAR LAND, 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 Rosenberg, TX — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00418728. Retrieved from https://blissgarden.com/texas/rosenberg.