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

Planting zone for 99716 — Two Rivers, AK

ZIP code 99716 (Two Rivers, Fairbanks North Star County) is in USDA zone 2a: the coldest winter night averages −50 to −45 °F. The median last spring frost is May 30 and the first fall frost September 2.

Where ZIP 99716 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.

Zone2a−50 to −45 °F
Coldest night−45.6 to −42.8 °C
Last frostMay 30
First frostSep 2
2012 zone2a

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 2a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Two Rivers, 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 Two Rivers, AK

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 30median — 50% chance of a later frost
Safe for tender plantsJune 13only 10% chance of frost after
First fall frostSeptember 2median — 10% chance by Aug 13
Growing season95 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 16 and returns around September 16.

From the NOAA station Two Rivers, AK — 2 miles away, elevation 604 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 99716

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 18 – May 2
SpinachSow outdoors · Apr 18 – May 9
Broccoli, cabbageStart indoors · Mar 21 – Apr 4
Broccoli, cabbageTransplant · May 9 – May 23
Onion setsPlant outdoors · May 2 – May 16
PotatoesPlant outdoors · May 9 – May 23
LettuceSow outdoors · May 2 – May 16
Carrots, beetsSow outdoors · May 9 – May 23
TomatoesStart indoors · Apr 4 – Apr 18
TomatoesTransplant · Jun 6 – Jun 20
Peppers, eggplantStart indoors · Mar 21 – Apr 4
Peppers, eggplantTransplant · Jun 13 – Jun 27
BeansSow outdoors · Jun 6 – Jun 20
Sweet cornSow outdoors · Jun 6 – Jun 20
Cucumbers, squashSow outdoors · Jun 6 – Jun 20
Fall lettuce, spinachSow outdoors · Jul 8 – Jul 22
GarlicPlant cloves · Aug 19 – Sep 23
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 30) and first fall frost (Sep 2) 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 2a in Alaska

44 plants native to Alaska, recorded in Alaska, and rated by the USDA to survive −50 °F or colder — the bottom of zone 2a. 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 16

alpine bearberry0.5 ft · blooms early spring · medium shade tolerance · to −62 °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 °Fmarsh Labrador tea0.5 ft · blooms summer · to −62 °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 Two Rivers, AK.

Soil in Two Rivers, AK

The soil mapped at the center of ZIP 99716 is Progress — slightly decomposed plant material, well drained.

TextureSlightly decomposed plant materialtop layer
pH5.3strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter90%high
Hydrologic groupBwater soaks in moderately
Farmland classFarmland of local importanceUSDA classification

Map unit: Progress silt loam, 0 to 3 percent slopes.

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 99716; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Two Rivers, AK

Summer high75 °Faverage high, July
Winter low−13 °Faverage low, January
Hot days0days a year at 90 °F or more
Freezing nights236nights a year at 32 °F or less
Growing degree days982base 50 °F — the season’s usable heat
Longest day21 h 53 mindaylight on June 21
Shortest day3 h 40 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation15.8 inper year, rain and melted snow
Snowfall61 inper year; 201 days with snow on the ground

Average high and low, by month

−20°−10°0°10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 6 °F, low -13 °F 6°−13° JanFebruary: average high 18 °F, low -4 °F 18°−4° FebMarch: average high 29 °F, low 1 °F 29°1° MarApril: average high 49 °F, low 22 °F 49°22° AprMay: average high 65 °F, low 34 °F 65°34° MayJune: average high 74 °F, low 45 °F 74°45° JunJuly: average high 75 °F, low 49 °F 75°49° JulAugust: average high 68 °F, low 44 °F 68°44° AugSeptember: average high 56 °F, low 34 °F 56°34° SepOctober: average high 36 °F, low 18 °F 36°18° OctNovember: average high 16 °F, low -2 °F 16°−2° NovDecember: average high 9 °F, low -10 °F 9°−10° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″January: 0.55 in precipitation, 10.5 in snowfall 0.6❄11 JanFebruary: 0.57 in precipitation, 6.9 in snowfall 0.6❄7 FebMarch: 0.39 in precipitation, 6 in snowfall 0.4❄6 MarApril: 0.40 in precipitation, 2.1 in snowfall 0.4❄2 AprMay: 1.02 in precipitation, 0.7 in snowfall 1.0❄1 MayJune: 2.41 in precipitation 2.4 JunJuly: 3.19 in precipitation 3.2 JulAugust: 3.13 in precipitation 3.1 AugSeptember: 1.95 in precipitation, 1.4 in snowfall 1.9❄1 SepOctober: 0.88 in precipitation, 12.1 in snowfall 0.9❄12 OctNovember: 0.73 in precipitation, 12.7 in snowfall 0.7❄13 NovDecember: 0.59 in precipitation, 9 in snowfall 0.6❄9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Two Rivers, AK (2 mi away); precipitation: Two Rivers, AK (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

997052a
North Pole, AK · 13 mi
997022a
Eielson Afb, AK · 16 mi
997032a
Fort Wainwright, AK · 21 mi
997102b
Fairbanks, AK · 24 mi
997112a
Fairbanks, AK · 24 mi
997073b
Fairbanks, AK · 27 mi
997752b
Fairbanks, AK · 28 mi
997082a
Fairbanks, AK · 29 mi

Alaska planting zones →

Questions about 99716

What planting zone is ZIP code 99716?

ZIP code 99716 (Two Rivers, AK) is in USDA hardiness zone 2a on the 2023 map: the coldest night of an average winter reaches −50 to −45 °F (−45.6 to −42.8 °C).

When is the last frost in Two Rivers, AK?

The median last spring frost (32 °F) near 99716 is May 30; after June 13 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Two Rivers station.

When is the first frost in Two Rivers, AK?

The median first fall frost near 99716 is September 2, giving a median frost-free growing season of 95 days.

When should I plant tomatoes in 99716?

Start tomato seeds indoors around Apr 4 – Apr 18 and set transplants outside around Jun 6 – Jun 20, one to three weeks after the median last frost.

How much rain and snow does 99716 get?

About 15.8 inches of precipitation a year and 61 inches of snowfall (NOAA 1991–2020 normals, Two Rivers station).

How hot do summers get in Two Rivers, AK?

The average high peaks at 75 °F in July, with about 0 days a year at 90 °F or more.

What kind of soil does 99716 have?

The USDA soil survey maps Progress at the center of ZIP 99716: slightly decomposed plant material, well drained, pH about 5.3 (strongly acidic).

What kind of onions grow in Two Rivers, AK?

Long-day onions: the longest day near 99716 is 21 h 53 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).