Planting zone for 96791 — Waialua, HI
ZIP code 96791 (Waialua, Honolulu County) is in USDA zone 12a: the coldest winter night averages 50 to 55 °F.
Where ZIP 96791 is
Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoomNot the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.
Was 12b on the 2012 map — half a zone colder now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 12a means →
Frost forecast — next 7 nights
live from the National Weather ServiceLoading the forecast for Waialua, HI…
Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.
Frost dates
Frost is rare or absent here: Waialua, HI is in zone 12a, where the coldest night of a typical winter stays above freezing. Cool-season vegetables grow best from fall through spring; summer heat, not frost, is the limit.
Native plants for zone 12a in Hawaii
37 plants native to Hawaii, recorded in Hawaii, and rated by the USDA to survive 50 °F or colder — the bottom of zone 12a. Each links to its USDA PLANTS profile.
Trees 7
Shrubs 12
Wildflowers & perennials 8
Grasses 10
Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in Waialua, HI.
Soil in Waialua, HI
The soil mapped at the center of ZIP 96791 is Kaena — stony clay, poorly drained.
Map unit: Kaena stony clay, 2 to 6 percent slopes.
Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 96791; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.
Climate in Waialua, HI
Average high and low, by month
Precipitation by month inches
NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Makaha Ctry Club 800.3, HI (6 mi away); precipitation: Makaha Ctry Club 800.3, HI (6 mi away). Daylight is calculated from latitude.
Nearby ZIP codes
3 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.
Questions about 96791
What planting zone is ZIP code 96791?
ZIP code 96791 (Waialua, HI) is in USDA hardiness zone 12a on the 2023 map: the coldest night of an average winter reaches 50 to 55 °F (10 to 12.8 °C).
How much rain and snow does 96791 get?
About 21.8 inches of precipitation a year (NOAA 1991–2020 normals, Makaha Ctry Club 800.3 station).
How hot do summers get in Waialua, HI?
The average high peaks at 86 °F in August, with about 1 days a year at 90 °F or more.
What kind of soil does 96791 have?
The USDA soil survey maps Kaena at the center of ZIP 96791: stony clay, poorly drained, pH about 7.0 (neutral).
What kind of onions grow in Waialua, HI?
Short-day onions: the longest day near 96791 is 13 h 27 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.
Did the zone for 96791 change?
Yes. The 2012 USDA map put 96791 in zone 12b; the 2023 map puts it in zone 12a. The newer map uses 1991–2020 data and more weather stations.