Zone 12b covers 137 ZIP codes in Hawaii and Puerto Rico on the 2023 map. Cities in it include Honolulu, Kahului and Kailua Kona in Hawaii and Ponce and Mayaguez in Puerto Rico.

Zone 12b Planting Calendar and Hardy Plants (55°F to 60°F)

Q: What does zone 12b mean?

Zone 12b means the coldest night of the winter averages 55°F to 60°F, measured over 1991 to 2020. It is an average of each winter's lowest temperature, so some winters go colder.

Q: Does zone 12b get frost?

Rarely. 26 of the 27 NOAA stations in zone 12b record no spring freeze in most years, so planting here runs by the season rather than a frost date.

Q: What can I plant in zone 12b?

4 of the plants listed here are rated for zone 12b by NC State Extension, including perennials such as bird of paradise and elephant ear (Alocasia) and fruit such as avocado and pineapple. Any plant rated for a range that includes 12b should come through a typical winter.

Q: What is the difference between zone 12a and 12b?

Five degrees. Zone 12a averages 50°F to 55°F and 12b averages 55°F to 60°F, so 12a is the colder half. A plant rated for zone 12 suits both.

Q: Will a plant rated for zone 12a grow in zone 12b?

Cold is no obstacle: zone 12b's coldest nights, 55°F to 60°F, are warmer than 12a's. A hardiness zone says nothing about heat or rainfall, so those decide instead.

137 ZIP codes

Where zone 12b is

Zone 12b covers 137 ZIP codes in Hawaii and Puerto Rico: Hawaii (95).

Across its 1 NOAA station the last spring frost comes around Jan 26 and the first fall frost around Jan 24. 26 more record no spring freeze in most years.

Cities and towns in zone 12b

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 12b planting calendar

What to start, sow, plant, divide, prune, mulch and protect in zone 12b, 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.

Most of zone 12b sees no frost to count from, so the vegetable months come straight from University of Hawaii at Manoa CTAHR Cooperative Extension’s Home Gardening in Hawaii for Hawaii's low elevations (0 to 1,000 feet).

Pick a month above to see every job in it.

The year at a glance

Plant vegetables: Low elevations (0 to 1,000 feet)all year

4 plants

What grows in zone 12b

Perennials, shrubs, trees and fruit that NC State Extension rates as hardy in zone 12b, 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 2

Bird of paradisezones 10a to 12b
Elephant ear (Alocasia)zones 10a to 12b

Fruit 2

Avocadozones 9a to 12b
Pineapplezones 10a to 12b

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 12b

Each half zone is five degrees. Zone 12a is five degrees colder at 50°F to 55°F. Zone 13a is five degrees warmer at 60°F to 65°F.

Zone 12a, colder50°F to 55°F Zone 13a, warmer60°F to 65°F

Questions

Zone 12b questions

What does zone 12b mean?

Where is zone 12b?

Does zone 12b get frost?

What can I plant in zone 12b?

What is the difference between zone 12a and 12b?

Will a plant rated for zone 12a grow in zone 12b?

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.