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

Planting zone for 99655 — Quinhagak, AK

ZIP code 99655 (Quinhagak, Bethel Census Area County) is in USDA zone 4b: the coldest winter night averages −25 to −20 °F. The median last spring frost is May 21 and the first fall frost September 22.

Where ZIP 99655 is

Outlined: the ZIP code area · 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.

Zone4b−25 to −20 °F
Coldest night−31.7 to −28.9 °C
Last frostMay 21
First frostSep 22
2012 zone4b

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 4b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Quinhagak, AK…

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 in Quinhagak, AK

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 21median — 50% chance of a later frost
Safe for tender plantsJune 2only 10% chance of frost after
First fall frostSeptember 22median — 10% chance by Sep 7
Growing season122 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 11 and returns around October 1.

From the NOAA station Bethel Airport, AK — 72 miles away, elevation 102 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 99655

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 9 – Apr 23
SpinachSow outdoors · Apr 9 – Apr 30
Broccoli, cabbageStart indoors · Mar 12 – Mar 26
Broccoli, cabbageTransplant · Apr 30 – May 14
Onion setsPlant outdoors · Apr 23 – May 7
PotatoesPlant outdoors · Apr 30 – May 14
LettuceSow outdoors · Apr 23 – May 7
Carrots, beetsSow outdoors · Apr 30 – May 14
TomatoesStart indoors · Mar 26 – Apr 9
TomatoesTransplant · May 28 – Jun 11
Peppers, eggplantStart indoors · Mar 12 – Mar 26
Peppers, eggplantTransplant · Jun 4 – Jun 18
BeansSow outdoors · May 28 – Jun 11
Sweet cornSow outdoors · May 28 – Jun 11
Cucumbers, squashSow outdoors · May 28 – Jun 11
Fall lettuce, spinachSow outdoors · Jul 28 – Aug 11
GarlicPlant cloves · Sep 8 – Oct 13
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 21) and first fall frost (Sep 22) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

Soil in Quinhagak, AK

The soil mapped at the center of ZIP 99655 is E38-maritime silty dwarf scrub-lichen frozen coastal plains — peat, poorly drained.

TexturePeattop layer
pH4.8strongly acidic; most vegetables like 6.0–7.0
DrainagePoorly drainedconsider raised beds
Organic matter80%high
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Yukon-Kuskokwim Coastal Plain-Maritime Lowland-Coastal Plains, High.

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 99655; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Quinhagak, AK

Summer high64 °Faverage high, July
Winter low1 °Faverage low, January
Hot days0days a year at 90 °F or more
Freezing nights214nights a year at 32 °F or less
Growing degree days501base 50 °F — the season’s usable heat
Longest day18 h 46 mindaylight on June 21
Shortest day5 h 57 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Average high and low, by month

−10°0°10°20°30°40°50°60°70°32 °FJanuary: average high 13 °F, low 1 °F 13°1° JanFebruary: average high 20 °F, low 7 °F 20°7° FebMarch: average high 22 °F, low 7 °F 22°7° MarApril: average high 37 °F, low 21 °F 37°21° AprMay: average high 52 °F, low 34 °F 52°34° MayJune: average high 62 °F, low 45 °F 62°45° JunJuly: average high 64 °F, low 49 °F 64°49° JulAugust: average high 61 °F, low 47 °F 61°47° AugSeptember: average high 53 °F, low 39 °F 53°39° SepOctober: average high 38 °F, low 26 °F 38°26° OctNovember: average high 24 °F, low 13 °F 24°13° NovDecember: average high 16 °F, low 4 °F 16°4° Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Bethel Airport, AK (72 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

Alaska planting zones →

Questions about 99655

What planting zone is ZIP code 99655?

ZIP code 99655 (Quinhagak, AK) is in USDA hardiness zone 4b on the 2023 map: the coldest night of an average winter reaches −25 to −20 °F (−31.7 to −28.9 °C).

When is the last frost in Quinhagak, AK?

The median last spring frost (32 °F) near 99655 is May 21; after June 2 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Bethel Airport station.

When is the first frost in Quinhagak, AK?

The median first fall frost near 99655 is September 22, giving a median frost-free growing season of 122 days.

When should I plant tomatoes in 99655?

Start tomato seeds indoors around Mar 26 – Apr 9 and set transplants outside around May 28 – Jun 11, one to three weeks after the median last frost.

How hot do summers get in Quinhagak, AK?

The average high peaks at 64 °F in July, with about 0 days a year at 90 °F or more.

What kind of soil does 99655 have?

The USDA soil survey maps E38-maritime silty dwarf scrub-lichen frozen coastal plains at the center of ZIP 99655: peat, poorly drained, pH about 4.8 (strongly acidic).

What kind of onions grow in Quinhagak, AK?

Long-day onions: the longest day near 99655 is 18 h 46 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).