What zone 12b means for Honolulu
Hardiness zones are based on the average of the coldest night of each winter over 30 years (1991 to 2020). In zone 12b, that average is 55 to 60°F (13 to 16°C). Plants labeled hardy to zone 12b or colder should survive a typical Honolulu winter. A plant rated only to a warmer zone will need a sheltered spot, a pot you can bring inside, or treating as an annual.
How Honolulu compares with the rest of Hawaii
Hawaii runs from zone 10b to zone 13a on the 2023 map. About 72% of the state's ZIP codes share Honolulu's zone 12b. Gardeners in colder parts of the state may need hardier plants, while those in warmer parts can grow some plants that would struggle here.
Choosing plants for zone 12b
When you shop, look for the hardiness range on the tag or in the catalog, such as "zones 4 to 9". Pick perennials, shrubs and trees whose range includes 12b. If you are set on a plant rated only to a warmer zone, plant it in a sheltered spot against a south-facing wall, mulch the roots before winter, or grow it in a container you can move into a garage. Zones only cover winter cold, so also check sun, water and soil needs. More in how to read a plant tag.
Honolulu ZIP codes and zones
ZIP codes GeoNames assigns to Honolulu, which can include PO box ZIP codes.
Frequently asked questions
What planting zone is Honolulu in?
Honolulu, HI is in USDA plant hardiness zone 12b. Zone 12b means an average coldest winter night of 55 to 60°F (13 to 16°C), based on the 2023 USDA map.
Did Honolulu's zone change in 2023?
The 2023 USDA map uses weather data from 1991 to 2020. The USDA says about half of the country shifted to the next warmer half zone compared with the 2012 map, while the rest stayed in the same half zone.
Zones: 2023 USDA Plant Hardiness Zone Map ZIP code listings, PRISM Climate Group, Oregon State University. Place names: GeoNames (CC BY 4.0). Not the official USDA map. Our data.