Honolulu, HI — USDA Zone 12b

Frost dates and growing season in Honolulu

All of Honolulu's mapped ZIP codes fall in the same hardiness band, Zone 12b.

These are 50%-probability averages modeled from Honolulu's USDA hardiness zone and regional climate normals — not a single-station reading. In a typical year the last spring frost will have passed by no frost, but a colder-than-average year can run 1-2 weeks later. Plant tender crops (tomatoes, peppers, basil) once both soil and night temperatures are consistently warm — a thermometer beats the calendar.

Growing season in Honolulu

Honolulu, Hawaii sits in USDA Zone 12b, with roughly 365 frost-free days between an average last spring frost around no frost and a first fall frost around no frost. That is a near year-round season — the limiting factor is summer heat, not frost, so schedule cool-season crops for winter and protect tender ones from extreme highs. Honolulu lies near 21.3°N; higher-latitude gardens get longer midsummer days but a tighter shoulder season at this zone.

What grows in Honolulu

Honolulu falls in USDA Zone 12b, so the same hardiness constraints apply as the full Zone 12 guide. Vegetables, herbs, and fruit trees rated to Zone 12b (or hardier) will overwinter here in a typical year.

• Mango, papaya, banana, breadfruit
• Cacao
• Coffee (mid-elevation)
• Coconut
• Pineapple
• Tropical greens
• Hot peppers
• Sweet potatoes
• Cassava
• Tropical herbs

What to plant in Honolulu this week

Warm-season tropicals do well in Honolulu right now. Watch for midsummer heat stress on tomatoes — short-day varieties or shade cloth help.

• When to plant tomatoes in zone 12
• When to plant peppers in zone 12
• When to plant basil in zone 12
• When to plant cucumbers in zone 12
• When to plant summer squash in zone 12

Full planting calendar for Honolulu

Crop-by-crop sowing, transplant, and harvest dates calibrated to zone 12 averages:

• When to plant tomatoes in zone 12
• When to plant peppers in zone 12
• When to plant basil in zone 12
• When to plant bush beans in zone 12
• When to plant cucumbers in zone 12
• When to plant summer squash in zone 12

ZIP codes in Honolulu

Drill down to the precise frost window and planting calendar for a specific ZIP in Honolulu:

• 96813 — Honolulu (Zone 12b)
• 96815 — Honolulu (Waikiki) (Zone 12b)
• 96818 — Honolulu (Salt Lake) (Zone 12b)
• 96822 — Honolulu (Manoa) (Zone 12a)

Local microclimate notes

Zone tables give you the average — but Honolulugardens vary. South-facing walls and paved areas can run a full half-zone warmer than the published rating. Low-lying spots, frost pockets, and shaded north sides can run colder. If you've gardened here a few seasons, your own frost record — the last time you actually got frost damage — beats any national average.

Source and methodology

Hardiness zone from the USDA Plant Hardiness Zone Map (2023 revision). Frost-date and growing-season figures are modeled from Honolulu's USDA hardiness zone and regional NOAA 1991-2020 climate normals — zone-level estimates, not a per-station record, so treat them as planning guidance and confirm against your own local frost history. Crop recommendations draw on US Cooperative Extension references, curated by the Growli editorial team. Last reviewed June 2026.

Other cities in Hawaii

• Ewa Beach, HI — USDA Zone 12b
• Hilo, HI — USDA Zone 12a
• Kahului, HI — USDA Zone 12b
• Kailua, HI — USDA Zone 12b
• Kailua-Kona, HI — USDA Zone 12a
• Kaneohe, HI — USDA Zone 12a
• Kapolei, HI — USDA Zone 12b
• Lihue, HI — USDA Zone 12b
• Wailuku, HI — USDA Zone 12b
• Waipahu, HI — USDA Zone 12b
• All of Hawaii by zone

Related guides

• USDA Zone 12 — full plant + frost guide
• Browse USDA hardiness zones by city
• Look up a ZIP code
• How to start a vegetable garden — beginner guide