Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 96733 — Kahului, HI

ZIP code 96733 (Kahului, Maui County) is in USDA zone 12b: the coldest winter night averages 55 to 60 °F.

Where ZIP 96733 is

tap the map for the zone at any spot · scroll or pinch to zoom

Not 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.

Zone12b55 to 60 °F
Coldest night12.8 to 15.6 °C
Last frostrare
First frostrare
2012 zone12b

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 12b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Kahului, 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: Kahului, HI is in zone 12b, 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 12b in Hawaii

37 plants native to Hawaii, recorded in Hawaii, and rated by the USDA to survive 55 °F or colder — the bottom of zone 12b. Each links to its USDA PLANTS profile.

Trees 7

Chamisso's manfern10 ft · blooms indeterminate · medium shade tolerance · to 40 °Fhapu'u8 ft · blooms indeterminate · medium shade tolerance · to 40 °FHawai'i pritchardia60 ft · medium shade tolerance · to 40 °FKamalo pritchardia16 ft · medium shade tolerance · to 40 °Fkoa110 ft · blooms spring · high shade tolerance · to 31 °Fkoaoha40 ft · blooms early spring · high shade tolerance · to 25 °F

Shrubs 12

'ala'a40 ft · medium shade tolerance · to 40 °F'ohi'a lehua65 ft · blooms late spring · high shade tolerance · to 22 °Fbeach naupaka10 ft · blooms indeterminate · medium shade tolerance · to 31 °FGaudichaud's senna2 ft · to 40 °FHawai'i desert-thorn1 ft · blooms summer · medium shade tolerance · to 40 °FHawai'i hawthorn12 ft · blooms spring · medium shade tolerance · to 35 °F

Wildflowers & perennials 8

bayhops1 ft · blooms indeterminate · medium shade tolerance · to 17 °Fbeach strawberry0.8 ft · blooms early spring · medium shade tolerance · to −33 °Fcommon duckmeatblooms late summer · medium shade tolerance · to −38 °Fcommon maidenhair1.7 ft · blooms summer · low shade tolerance · to −33 °Flongleaf pondweedblooms mid summer · high shade tolerance · to −38 °Fsalt heliotrope1.2 ft · blooms mid spring · high shade tolerance · to −28 °F

Grasses 10

blunt spikerush1.6 ft · blooms summer · high shade tolerance · to 37 °Fcosmopolitan bulrush3 ft · blooms late summer · high shade tolerance · to −23 °Ffragrant flatsedge2 ft · blooms late summer · high shade tolerance · to 42 °Fkawelu3 ft · high shade tolerance · to 40 °Fmanyspike flatsedge1.6 ft · blooms mid summer · high shade tolerance · to 47 °Fovate spikerush1.5 ft · blooms late summer · high shade tolerance · to 47 °F

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 Kahului, HI.

Soil in Kahului, HI

The soil mapped at the center of ZIP 96733 is Puuone — sand, somewhat excessively drained.

TextureSanddrains and warms fast; dries out and needs more feeding
pH8.2alkaline; most vegetables like 6.0–7.0
DrainageSomewhat excessively drainednatural drainage class
Organic matter0.3%low — add compost
Hydrologic groupAwater soaks in fast
Farmland classNot prime farmlandUSDA classification

Map unit: Puuone sand, 7 to 30 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 96733; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Kahului, HI

Summer high90 °Faverage high, August
Winter low64 °Faverage low, January
Hot days39days a year at 90 °F or more
Freezing nights0nights a year at 32 °F or less
Growing degree days9,898base 50 °F — the season’s usable heat
Longest day13 h 24 mindaylight on June 21
Shortest day10 h 52 mindaylight on December 21
Onions to growShort-daysummer days stay under about 14 h 20 min, so long-day varieties won’t bulb
Precipitation33.5 inper year, rain and melted snow

Average high and low, by month

50°60°70°80°90°100°January: average high 82 °F, low 64 °F 82°64° JanFebruary: average high 82 °F, low 64 °F 82°64° FebMarch: average high 83 °F, low 65 °F 83°65° MarApril: average high 85 °F, low 67 °F 85°67° AprMay: average high 87 °F, low 68 °F 87°68° MayJune: average high 88 °F, low 70 °F 88°70° JunJuly: average high 89 °F, low 72 °F 89°72° JulAugust: average high 90 °F, low 72 °F 90°72° AugSeptember: average high 90 °F, low 71 °F 90°71° SepOctober: average high 89 °F, low 70 °F 89°70° OctNovember: average high 86 °F, low 68 °F 86°68° NovDecember: average high 83 °F, low 66 °F 83°66° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 4.67 in precipitation 4.7 JanFebruary: 3.90 in precipitation 3.9 FebMarch: 4.64 in precipitation 4.6 MarApril: 3.12 in precipitation 3.1 AprMay: 2.20 in precipitation 2.2 MayJune: 0.67 in precipitation 0.7 JunJuly: 1.57 in precipitation 1.6 JulAugust: 1.43 in precipitation 1.4 AugSeptember: 1.53 in precipitation 1.5 SepOctober: 2.17 in precipitation 2.2 OctNovember: 3.48 in precipitation 3.5 NovDecember: 4.15 in precipitation 4.2 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Kahului Airport, HI (3 mi away); precipitation: Waiehu Camp 484, HI (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

1 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

9673212b
Kahului, HI · 1 mi
9679312b
Wailuku, HI · 4 mi
9677912b
Paia, HI · 6 mi
9676112b
Lahaina, HI · 9 mi
9678812a
Pukalani, HI · 10 mi
9676712b
Lahaina, HI · 11 mi
9678412b
Puunene, HI · 11 mi
9675312b
Kihei, HI · 11 mi

All 2 ZIP codes in Kahului → · Hawaii planting zones →

Questions about 96733

What planting zone is ZIP code 96733?

ZIP code 96733 (Kahului, HI) is in USDA hardiness zone 12b on the 2023 map: the coldest night of an average winter reaches 55 to 60 °F (12.8 to 15.6 °C).

How much rain and snow does 96733 get?

About 33.5 inches of precipitation a year (NOAA 1991–2020 normals, Waiehu Camp 484 station).

How hot do summers get in Kahului, HI?

The average high peaks at 90 °F in August, with about 39 days a year at 90 °F or more.

What kind of soil does 96733 have?

The USDA soil survey maps Puuone at the center of ZIP 96733: sand, somewhat excessively drained, pH about 8.2 (alkaline).

What kind of onions grow in Kahului, HI?

Short-day onions: the longest day near 96733 is 13 h 24 min, so summer days stay under about 14 h 20 min, so long-day varieties won’t bulb.