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

Planting zone for 99710 — Fairbanks, AK

ZIP code 99710 (Fairbanks, Fairbanks North Star County) is in USDA zone 2b: the coldest winter night averages −45 to −40 °F. The median last spring frost is May 16 and the first fall frost September 6.

Where ZIP 99710 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.

Zone2b−45 to −40 °F
Coldest night−42.8 to −40 °C
Last frostMay 16
First frostSep 6
2012 zone2a

Was 2a on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 2b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Fairbanks, 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 Fairbanks, AK

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 16median — 50% chance of a later frost
Safe for tender plantsMay 29only 10% chance of frost after
First fall frostSeptember 6median — 10% chance by Aug 25
Growing season112 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 7 and returns around September 18.

From the NOAA station Aurora, AK — within 1 mile, elevation 443 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 99710

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 4 – Apr 18
SpinachSow outdoors · Apr 4 – Apr 25
Broccoli, cabbageStart indoors · Mar 7 – Mar 21
Broccoli, cabbageTransplant · Apr 25 – May 9
Onion setsPlant outdoors · Apr 18 – May 2
PotatoesPlant outdoors · Apr 25 – May 9
LettuceSow outdoors · Apr 18 – May 2
Carrots, beetsSow outdoors · Apr 25 – May 9
TomatoesStart indoors · Mar 21 – Apr 4
TomatoesTransplant · May 23 – Jun 6
Peppers, eggplantStart indoors · Mar 7 – Mar 21
Peppers, eggplantTransplant · May 30 – Jun 13
BeansSow outdoors · May 23 – Jun 6
Sweet cornSow outdoors · May 23 – Jun 6
Cucumbers, squashSow outdoors · May 23 – Jun 6
Fall lettuce, spinachSow outdoors · Jul 12 – Jul 26
GarlicPlant cloves · Aug 23 – Sep 27
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 16) and first fall frost (Sep 6) 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.

Native plants for zone 2b in Alaska

45 plants native to Alaska, recorded in Alaska, and rated by the USDA to survive −45 °F or colder — the bottom of zone 2b. Each links to its USDA PLANTS profile.

Trees 8

balsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °Fblack spruce65 ft · blooms late spring · low shade tolerance · to −79 °Flodgepole pine99 ft · blooms mid summer · high shade tolerance · to −70 °Fpaper birch70 ft · blooms mid spring · high shade tolerance · to −62 °Fquaking aspen65 ft · blooms mid spring · high shade tolerance · to −70 °Fsubalpine fir90 ft · blooms late spring · low shade tolerance · to −51 °F

Shrubs 17

alpine bearberry0.5 ft · blooms early spring · medium shade tolerance · to −62 °Fblack hawthorn15 ft · blooms mid spring · medium shade tolerance · to −47 °Fhalberd willow3 ft · blooms early summer · to −62 °FLapland rosebay3 ft · blooms late spring · low shade tolerance · to −62 °Flingonberry0.5 ft · blooms summer · high shade tolerance · to −62 °FMacKenzie's willow45 ft · blooms early spring · high shade tolerance · to −50 °F

Wildflowers & perennials 12

alpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °Farctic dock1 ft · blooms summer · high shade tolerance · to −62 °Farctic lupine2 ft · blooms spring · medium shade tolerance · to −62 °Farctic poppy1.5 ft · blooms summer · low shade tolerance · to −54 °Farctic raspberry1 ft · blooms summer · high shade tolerance · to −62 °Feightpetal mountain-avens0.3 ft · blooms late spring · medium shade tolerance · to −62 °F

Grasses 6

arctic bluegrass2 ft · high shade tolerance · to −62 °FHoppner's sedge1 ft · high shade tolerance · to −52 °Flargeflower speargrass2 ft · high shade tolerance · to −52 °Flivid sedge1 ft · blooms early summer · high shade tolerance · to −62 °FLyngbye's sedge1 ft · high shade tolerance · to −52 °FRamensk's sedge1 ft · high shade tolerance · to −52 °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 Fairbanks, AK.

Soil in Fairbanks, AK

The center of ZIP 99710 is mapped as Urban land: built-over ground without natural soil data. Garden soil here is usually imported or disturbed — test before you plant.

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 99710; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Fairbanks, AK

Summer high73 °Faverage high, July
Winter low−15 °Faverage low, January
Hot days0days a year at 90 °F or more
Freezing nights227nights a year at 32 °F or less
Growing degree days1,010base 50 °F — the season’s usable heat
Longest day21 h 50 mindaylight on June 21
Shortest day3 h 41 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation13 inper year, rain and melted snow
Snowfall58 inper year; 186 days with snow on the ground

Average high and low, by month

−30°−20°−10°0°10°20°30°40°50°60°70°80°32 °FJanuary: average high 0 °F, low -15 °F 0°−15° JanFebruary: average high 13 °F, low -9 °F 13°−9° FebMarch: average high 27 °F, low 0 °F 27°0° MarApril: average high 47 °F, low 21 °F 47°21° AprMay: average high 63 °F, low 37 °F 63°37° MayJune: average high 72 °F, low 49 °F 72°49° JunJuly: average high 73 °F, low 52 °F 73°52° JulAugust: average high 66 °F, low 46 °F 66°46° AugSeptember: average high 55 °F, low 35 °F 55°35° SepOctober: average high 34 °F, low 18 °F 34°18° OctNovember: average high 12 °F, low -3 °F 12°−3° NovDecember: average high 3 °F, low -11 °F 3°−11° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″January: 0.57 in precipitation, 8.7 in snowfall 0.6❄9 JanFebruary: 0.44 in precipitation, 9.6 in snowfall 0.4❄10 FebMarch: 0.34 in precipitation, 6.1 in snowfall 0.3❄6 MarApril: 0.34 in precipitation, 2.8 in snowfall 0.3❄3 AprMay: 0.64 in precipitation, 0.2 in snowfall 0.6 MayJune: 2.01 in precipitation 2.0 JunJuly: 2.62 in precipitation 2.6 JulAugust: 2.44 in precipitation 2.4 AugSeptember: 1.59 in precipitation, 1.3 in snowfall 1.6❄1 SepOctober: 0.77 in precipitation, 5.4 in snowfall 0.8❄5 OctNovember: 0.72 in precipitation, 13.2 in snowfall 0.7❄13 NovDecember: 0.53 in precipitation, 10.5 in snowfall 0.5❄11 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Aurora, AK (within 1 mile); precipitation: Aurora, AK (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

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

997112a
Fairbanks, AK · <1 mi
997032a
Fort Wainwright, AK · 3 mi
997752b
Fairbanks, AK · 4 mi
997082a
Fairbanks, AK · 9 mi
997253b
Ester, AK · 9 mi
997093b
Fairbanks, AK · 13 mi
997052a
North Pole, AK · 14 mi
997022a
Eielson Afb, AK · 24 mi

All 10 ZIP codes in Fairbanks → · Alaska planting zones →

Questions about 99710

What planting zone is ZIP code 99710?

ZIP code 99710 (Fairbanks, AK) is in USDA hardiness zone 2b on the 2023 map: the coldest night of an average winter reaches −45 to −40 °F (−42.8 to −40 °C).

When is the last frost in Fairbanks, AK?

The median last spring frost (32 °F) near 99710 is May 16; after May 29 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Aurora station.

When is the first frost in Fairbanks, AK?

The median first fall frost near 99710 is September 6, giving a median frost-free growing season of 112 days.

When should I plant tomatoes in 99710?

Start tomato seeds indoors around Mar 21 – Apr 4 and set transplants outside around May 23 – Jun 6, one to three weeks after the median last frost.

How much rain and snow does 99710 get?

About 13 inches of precipitation a year and 58 inches of snowfall (NOAA 1991–2020 normals, Aurora station).

How hot do summers get in Fairbanks, AK?

The average high peaks at 73 °F in July, with about 0 days a year at 90 °F or more.

What kind of onions grow in Fairbanks, AK?

Long-day onions: the longest day near 99710 is 21 h 50 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 99710 change?

Yes. The 2012 USDA map put 99710 in zone 2a; the 2023 map puts it in zone 2b. The newer map uses 1991–2020 data and more weather stations.