Sienna Plantation, TX planting zone & frost dates

Sienna Plantation is in USDA hardiness zone 9b. The last spring frost usually comes around February 15 and the first fall frost around December 6, for a growing season of about 297 days.

USDA hardiness zone9bavg. extreme winter low 25°F to 30°F
Average last spring frostFebruary 1590% chance of no frost after March 15
Average first fall frostDecember 610% chance of frost by November 13
Growing season297 daysfrost-free days in an average year

Planting calendar for Sienna Plantation

Dates are counted from the average last spring frost (February 15) using the typical timing recommended by U.S. extension services. Warm-season crops go out only after the danger of frost has passed and the soil has warmed.

CropWhen
TomatoesStart seeds indoors: Dec 21 – Jan 4
Transplant outdoors: Feb 22 – Mar 1
PeppersStart seeds indoors: Dec 7 – Dec 21
Transplant outdoors: Mar 1 – Mar 8
EggplantStart seeds indoors: Dec 7 – Dec 21
Transplant outdoors: Mar 1 – Mar 8
BroccoliStart seeds indoors: Dec 7 – Dec 21
Transplant outdoors: Jan 18 – Feb 1
CabbageStart seeds indoors: Dec 7 – Dec 21
Transplant outdoors: Jan 18 – Feb 1
Onions (sets)Plant outdoors: Jan 18 – Feb 1
PeasSow outdoors: Jan 4 – Jan 18
SpinachSow outdoors: Jan 4 – Jan 18
LettuceSow outdoors: Jan 18 – Feb 1
CarrotsSow outdoors: Jan 18 – Feb 1
PotatoesPlant outdoors: Jan 18 – Feb 1
BeansSow outdoors: Feb 22 – Mar 1
Sweet cornSow outdoors: Feb 22 – Mar 1
CucumbersSow outdoors: Feb 22 – Mar 1
Squash & zucchiniSow outdoors: Feb 22 – Mar 1
BasilStart seeds indoors: Jan 4 – Jan 18
Transplant outdoors: Feb 22 – Mar 1

Fall garden: cool-season crops like lettuce, spinach and kale can be sown again around Oct 11 (8 weeks before the average first fall frost on Dec 6).

Useful for zone 9b gardens

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Frost risk in detail

90% chance50% chance10% chance
Last 32°F frost in spring is afterJan 13Feb 15Mar 15
First 32°F frost in fall is beforeJan 5Dec 6Nov 13

How to read it: in spring there is a 10% chance of a frost after March 15, so that is a safe date for tender plants. In fall there is a 10% chance of frost before November 13. A hard freeze (28°F) usually ends around January 26.

Nearby cities

All cities in Texas → · Other zone 9b cities →

Questions

What growing zone is Sienna Plantation, TX?

Sienna Plantation is in USDA Plant Hardiness Zone 9b (average extreme winter low 25°F to 30°F), according to the USDA 2023 map.

When is the last frost in Sienna Plantation?

The average last spring frost (32°F) in Sienna Plantation is February 15. There is still a 10% chance of frost until March 15.

When can I plant tomatoes in Sienna Plantation?

Transplant tomatoes outdoors 1–2 weeks after the average last frost: around Feb 22 – Mar 1. Start seeds indoors 6–8 weeks before the last frost.

Frost dates: NOAA U.S. Climate Normals 1991–2020, station Thompsons 3 Wsw, TX (USC00418996), 12.0 km (7.5 mi) from the city center, elevation 21 m, based on 27 years of records. Hardiness zone: USDA Plant Hardiness Zone Map 2023 for the ZIP code nearest to the city center. Microclimates (valleys, hills, cities, coasts) can be warmer or colder: check the local forecast before planting. How we calculate the data.