Mauna Loa 5 NNE, HI Frost Dates & Growing Season

The two dates every Mauna Loa 5 NNE garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
Apr 12
~50% chance of frost after
First fall frost
Dec 1
~50% chance of frost before
Growing season
233 days
frost-free stretch
USDA zone
≈ 12a
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Mar 13 Apr 12 May 18
First fall frost Jan 7 Dec 1 Nov 9
Hard freeze (28°F), median last Feb 13 · first Jan 22

Computed from NOAA 1991–2020 climate normals at the MAUNA LOA 5 NNE station. "Safe" means frost past that date happens only about one year in ten. Your exact garden can still run days either way with elevation and terrain — check your own ZIP with the frost date lookup.

Planting windows for Mauna Loa 5 NNE

Computed from Mauna Loa 5 NNE's own frost dates. Click any crop for the full zone-12 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Feb 15 – Mar 1 Apr 19 – Apr 26
🫑 Peppers Feb 1 – Feb 15 Apr 26 – May 3
🥬 Lettuce Mar 1 – Mar 15 Mar 15 – Mar 29 Mar 15 – Apr 12
🫛 Peas Mar 1 – Mar 15
🥕 Carrots Mar 22 – Apr 12
🥦 Broccoli Feb 22 – Mar 8 Mar 22 – Apr 5
🥬 Kale Mar 1 – Mar 15 Mar 15 – Mar 29 Mar 15 – Mar 29
🥒 Cucumbers Mar 15 – Mar 22 Apr 19 – Apr 26 Apr 19 – Apr 26
🥒 Zucchini Mar 15 – Mar 22 Apr 19 – Apr 26 Apr 19 – Apr 26
🫘 Green Beans (Bush) Apr 19 – Apr 26
🌽 Sweet Corn Apr 19 – Apr 26
🌿 Basil Mar 1 – Mar 15 Apr 19 – Apr 26 Apr 26 – May 3
🧄 Garlic Fall: Oct 20 – Nov 17

Want this for all 50 crops, or as a printable seed-shelf schedule? Use the planting calendar and the seed starting scheduler — both can use Mauna Loa 5 NNE's dates automatically after a lookup.

Reading the season in Mauna Loa 5 NNE

With roughly 233 frost-free days, Mauna Loa 5 NNE gardens fit long-season crops — melons, winter squash, sweet potatoes — with room left for spring and fall rounds of greens and roots. The first frost around Dec 1 is late enough that fall planting is a full second season, not an afterthought.

Frequently asked questions

When is the last frost in Mauna Loa 5 NNE, HI?

The average last spring frost in Mauna Loa 5 NNE is around Apr 12, based on 1991–2020 climate normals. That's a median — about half of years see a later frost, so tender crops are safest going out a week or two after this date.

When is the first frost in Mauna Loa 5 NNE, HI?

The average first fall frost in Mauna Loa 5 NNE arrives around Dec 1. Crops still in the garden need to mature before then, and frost-tender plants need harvesting or protection as the date approaches.

How long is the growing season in Mauna Loa 5 NNE?

About 233 frost-free days on average, from Apr 12 to Dec 1. That comfortably fits long-season crops like melons and winter squash, plus spring and fall plantings of cool-season vegetables.

What USDA zone is Mauna Loa 5 NNE in?

USDA zone 12a on the 2023 Plant Hardiness Zone Map. Note that zones describe winter cold, not frost timing — these frost dates are the numbers to plan plantings around.