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USDA Hardiness Zone 12a

Frost Dates for 96760 — Kurtistown, Hawaii

Averages from Mauna Loa 5 Nne, Hi US, the nearest reporting station, 33.9 miles away.

Plant tender crops after April 12, and expect the first autumn freeze around December 1. That leaves about 235 frost-free days.

Last spring frost
April 12

50% probability

First fall frost
December 1

50% probability

Growing season
235 days

frost-free

Hardiness zone
12a

50 to 55°F annual low

Planting calendar for 96760

What to do and when, based on the frost normals for Kurtistown, Hawaii
WhenWhat to do
February 1 – February 15

Start peppers and aubergines indoors

They need eight to ten weeks under lights before they can go out.

February 15 – March 1

Start tomatoes indoors

Six to eight weeks gives a transplant big enough to set fruit early.

March 15 – March 29

Sow peas, spinach, lettuce, radish outdoors

These tolerate light frost and prefer to germinate in cool soil.

April 12 onward

Transplant tomatoes, peppers, basil, squash, cucumbers

The average last freeze has passed — still watch the actual forecast.

by September 8

Sow the autumn crop of carrots, beets and brassicas

They need about twelve weeks to size up before growth stops.

by November 17

Harvest tender crops, or be ready to cover them

A first freeze two weeks early is well within normal variation.

December 1 onward

Plant garlic, mulch beds, lift tender bulbs

Garlic wants a cold spell; bare soil loses structure over winter.

What these dates mean

Wait until after April 12 to put tender plants — tomatoes, peppers, basil, squash — in the ground. That is the date by which half of years in Kurtistown, Hawaii are past their last freeze. Harvest before December 1, which leaves roughly 235 frost-free days.

ZIP 96760 sits in USDA hardiness zone 12a, meaning the average coldest night of the year falls between 50 to 55°F. Zone decides what survives the winter; frost dates decide when to plant each spring. They are different questions, and a plant can pass one and fail the other.

These are thirty-year NOAA averages for 1991–2020, not a forecast. Any individual year can frost two to three weeks either side of these dates, so check the actual forecast before planting out.

Other zone 12a ZIP codes in Hawaii