Zone 9b covers 2,085 ZIP codes in 10 states on the 2023 map, most of them in California, Texas, Florida, Arizona and Louisiana. Cities in it include Houston in Texas, New Orleans in Louisiana, Las Vegas in Nevada, Tucson in Arizona and Sacramento in California.

Zone 9b Planting Calendar and Hardy Plants (25°F to 30°F)

Q: What does zone 9b mean?

Zone 9b means the coldest night of the winter averages 25°F to 30°F, measured over 1991 to 2020. It is an average of each winter's lowest temperature, so some winters go colder.

Q: When is the last frost in zone 9b?

Across 223 NOAA stations in zone 9b, the median last spring frost is Feb 4 and the median first fall frost is Dec 13. Half the stations fall between Jan 29 and Feb 18 in spring, so check the date for your own ZIP before you plant.

Q: What can I plant in zone 9b?

48 of the plants listed here are rated for zone 9b by NC State Extension, including perennials such as orange coneflower (black-eyed Susan), daylily and hosta and fruit such as apple, peach and garden strawberry. Any plant rated for a range that includes 9b should come through a typical winter.

Q: What is the difference between zone 9a and 9b?

Five degrees. Zone 9a averages 20°F to 25°F and 9b averages 25°F to 30°F, so 9a is the colder half. A plant rated for zone 9 suits both.

Q: Will a plant rated for zone 10a survive in zone 9b?

Not reliably. A plant rated down to 10a is rated for winter lows of 30°F to 35°F, and a typical zone 9b winter reaches 25°F to 30°F. Choose plants whose range on the tag includes 9b.

2,085 ZIP codes

Where zone 9b is

Zone 9b covers 2,085 ZIP codes in 10 states: California (879), Texas (423), Florida (333), Arizona (203), Louisiana (170), Nevada (60), Oregon (11), South Carolina (4) and 2 more.

Across its 223 NOAA stations the last spring frost comes around Feb 4 and the first fall frost around Dec 13; half the stations fall between Jan 29 and Feb 18 in spring and Dec 5 and Dec 24 in fall. 1 more record no spring freeze in most years.

Cities and towns in zone 9b

Tap a town for its own frost dates and this month’s jobs; a hill or a valley a few miles off can be half a zone either side.

Twelve months

Zone 9b planting calendar

What to start, sow, plant, divide, prune, mulch and protect in zone 9b, month by month. Every job names the extension service page it rests on; open “Where this comes from” under a job to read their words.

Timed from the median frost dates of the 223 NOAA stations in zone 9b: last spring frost Feb 4, first fall frost Dec 13. Your own ZIP’s frost dates move every window, so the ZIP tool times them for you. In Florida, Arizona’s low desert, Southern Nevada, South Louisiana and California’s inland valleys, the state pages and the ZIP tool use those extension services’ own vegetable planting months.

Pick a month above to see every job in it.

The year at a glance

Start vegetable seeds indoorsOct to Jan
Sow vegetables in the gardenJan to Feb
Sow the fall vegetable gardenAug to Oct
Set out transplantsJan to Feb
Plant trees and shrubsNov 1 to Feb 18
Plant garlicNov 29 to Jan 3
Plant pre-chilled tulip bulbsNov 20 to Dec 31
Divide fall-blooming perennialsJan 14 to Feb 25
Divide spring and summer-blooming perennialsNov 1 to Dec 13
Prune trees and summer-flowering shrubs while dormantDec 24 to Feb 4
Prune spring-flowering shrubs after they bloomJan 21 to Mar 18
Prune out cold damageFeb 4 to Mar 18
Cover tender plants on a freezing nightDec 6 to Feb 4
Cut back perennials after a hard freezeDec 20 to Jan 17

48 plants

What grows in zone 9b

Perennials, shrubs, trees and fruit that NC State Extension rates as hardy in zone 9b, each linked to its plant page. A plant rated for a range of zones suits every half zone in it, so “zones 4 to 8” covers 4a through 8b.

Perennials 11

Orange coneflower (black-eyed Susan)zones 3a to 9b
Daylilyzones 3a to 9b
Hostazones 3a to 9b
Catmintzones 5a to 9b
Coral bells (American alumroot)zones 4a to 9b
Butterfly weedzones 3a to 9b
Blue false indigozones 3a to 9b
Yarrowzones 3a to 9b
English lavenderzones 5a to 9b
Showy stonecrop (sedum)zones 4a to 9b
Rose mallowzones 4a to 9b

Shrubs 11

Smooth hydrangeazones 3a to 9b
Bigleaf hydrangeazones 6a to 11b
Winterberry hollyzones 3a to 9b
Japanese camelliazones 7a to 9b
Gardeniazones 7b to 11b
Chinese fringe flower (loropetalum)zones 7b to 9b
Tropical hibiscuszones 9a to 11b
Bougainvilleazones 9b to 10b
Oleanderzones 8a to 10b
Rose of Sharonzones 5a to 9b
Ixorazones 9a to 11b

Trees 7

Crape myrtlezones 6a to 9b
Red maplezones 2a to 9b
Eastern redbudzones 4a to 9b
Flowering dogwoodzones 5a to 9b
Southern magnoliazones 6a to 10b
Live oakzones 8a to 10b
Cabbage palmettozones 7b to 11b

Fruit 13

Applezones 4a to 9b
Peachzones 5a to 9b
Garden strawberryzones 5a to 9b
Muscadine grapezones 5a to 9b
Figzones 7a to 10b
American persimmonzones 4a to 9b
Pawpawzones 5a to 9b
Lemonzones 9a to 11b
Avocadozones 9a to 12b
Loquatzones 8a to 11b
Pomegranatezones 8a to 10b
Olivezones 8a to 10b
Pineapple guava (feijoa)zones 8a to 10b

Bulbs 4

Cannazones 6a to 10b
Dahliazones 7a to 10b
Gladioluszones 7a to 10b
Elephant ear (Colocasia)zones 8a to 11b

Perennial vegetables 2

Garliczones 4a to 9b
Asparaguszones 2a to 9b

Ratings from the NC State Extension Gardener Plant Toolbox, read Oct 9, 2026. The zone covers winter cold only; heat, rain and soil decide the rest.

A summer perennial border of yellow black-eyed Susans, purple liatris spikes and silvery Russian sage, with a rose of Sharon shrub behind and small plant labels in the bed — A labeled perennial border in high summer. The zone on a plant tag is the coldest winter it is rated to come through, so a plant rated for zones 4 to 9 suits every half zone from 4a to 9b. “Perennials border in Summer”, Bindersbee, Public domain

Either side

The zones next to 9b

Each half zone is five degrees. Zone 9a is five degrees colder at 20°F to 25°F. Zone 10a is five degrees warmer at 30°F to 35°F.

Zone 9a, colder20°F to 25°F Zone 10a, warmer30°F to 35°F

Questions

Zone 9b questions

What does zone 9b mean?

Where is zone 9b?

When is the last frost in zone 9b?

What can I plant in zone 9b?

What is the difference between zone 9a and 9b?

Will a plant rated for zone 10a survive in zone 9b?

Your own dates, by ZIP

Find your zone by ZIPYour zone, your frost dates and this month’s jobs for your address.Seed starting calendarWhen to start each vegetable indoors, by ZIP.Frost dates by ZIPYour last spring and first fall frost, with the odds either side.First frost forecastWhen the first fall frost usually arrives, state by state.Soil temperatureWhen the ground is warm enough to sow.When to plant garlicThe fall planting window by ZIP.

Sources. USDA Plant Hardiness Zone Map, ZIP code tables (2023 and 2012), PRISM Climate Group, Oregon State University; USDA Plant Hardiness Zone Map; USDA Unveils Updated Plant Hardiness Zone Map (USDA Agricultural Research Service, November 15, 2023); NOAA NCEI U.S. Climate Normals 1991-2020, annual/seasonal, by station (v1.0.1); NC State Extension Gardener Plant Toolbox. Zone frost dates are the medians of the NOAA 1991 to 2020 station normals inside the zone.

The calendar’s extension sources:

UNH Cooperative Extension, Growing Vegetables: When to Plant your Vegetable Garden, read Sep 21, 2026.
University of Minnesota Extension, Planting vegetables in midsummer for a fall harvest, read Oct 9, 2026.
University of Illinois Extension, Planting a fall vegetable garden (Good Growing), read Oct 9, 2026.
University of Minnesota Extension, Dividing perennials, read Oct 9, 2026.
Iowa State University Extension and Outreach, How should I prepare my perennial beds for winter?, read Oct 9, 2026.
University of Minnesota Extension, Pruning trees and shrubs, read Oct 9, 2026.
Rutgers NJAES Cooperative Extension, Pruning Flowering Shrubs (FS1221), read Oct 9, 2026.
University of Maryland Extension, Planting a Tree or Shrub, read Oct 9, 2026.
University of Wisconsin-Madison Division of Extension, Preparing Landscape Plants for Winter, read Oct 9, 2026.
University of Wisconsin-Madison Division of Extension, Storing Tender Bulbs for Winter, read Oct 9, 2026.
Iowa State University Extension and Outreach, All About Tulips, read Oct 9, 2026.
UF/IFAS Gardening Solutions, Tulips, read Oct 9, 2026.
UF/IFAS Gardening Solutions, Preparing the Landscape for Cold Weather, read Oct 9, 2026.
UF/IFAS Gardening Solutions, Treating Cold-Damaged Plants, read Oct 9, 2026.