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

Planting zone for 99689 — Yakutat, AK

ZIP code 99689 (Yakutat, Skagway-Hoonah-Angoon County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is May 20 and the first fall frost September 23.

Where ZIP 99689 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostMay 20
First frostSep 23
2012 zone6b

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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Yakutat, 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 Yakutat, AK

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 20median — 50% chance of a later frost
Safe for tender plantsMay 31only 10% chance of frost after
First fall frostSeptember 23median — 10% chance by Sep 5
Growing season124 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 1 and returns around October 7.

From the NOAA station Yakutat State Airport, AK — 9 miles away, elevation 33 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 99689

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Apr 8 – Apr 22
SpinachSow outdoors · Apr 8 – Apr 29
Broccoli, cabbageStart indoors · Mar 11 – Mar 25
Broccoli, cabbageTransplant · Apr 29 – May 13
Onion setsPlant outdoors · Apr 22 – May 6
PotatoesPlant outdoors · Apr 29 – May 13
LettuceSow outdoors · Apr 22 – May 6
Carrots, beetsSow outdoors · Apr 29 – May 13
TomatoesStart indoors · Mar 25 – Apr 8
TomatoesTransplant · May 27 – Jun 10
Peppers, eggplantStart indoors · Mar 11 – Mar 25
Peppers, eggplantTransplant · Jun 3 – Jun 17
BeansSow outdoors · May 27 – Jun 10
Sweet cornSow outdoors · May 27 – Jun 10
Cucumbers, squashSow outdoors · May 27 – Jun 10
Fall lettuce, spinachSow outdoors · Jul 29 – Aug 12
GarlicPlant cloves · Sep 9 – Oct 14
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 20) and first fall frost (Sep 23) 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 6b in Alaska

286 plants native to Alaska, recorded in Alaska, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. Each links to its USDA PLANTS profile.

Trees 16

Alaska cedar75 ft · blooms mid spring · low shade tolerance · to −22 °Fbalsam 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 °Fmountain hemlock125 ft · blooms early summer · low shade tolerance · to −18 °FPacific silver fir165 ft · blooms late spring · low shade tolerance · to −28 °F

Shrubs 49

alpine bearberry0.5 ft · blooms early spring · medium shade tolerance · to −62 °Falpine laurel1 ft · blooms late spring · low shade tolerance · to −28 °FBarclay's willow15 ft · high shade tolerance · to −43 °Fblack crowberry1 ft · blooms mid summer · high shade tolerance · to −43 °Fblack hawthorn15 ft · blooms mid spring · medium shade tolerance · to −47 °Fbog blueberry2 ft · blooms early summer · medium shade tolerance · to −38 °F

Wildflowers & perennials 124

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine aster0.3 ft · blooms early summer · medium shade tolerance · to −28 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine mountainsorrel1 ft · blooms mid summer · medium shade tolerance · to −43 °Falpine sweetvetch2 ft · blooms early summer · high shade tolerance · to −62 °FAmerican alpine speedwell1 ft · blooms summer · medium shade tolerance · to −28 °F

Grasses 88

Alaska brome5 ft · blooms late spring · low shade tolerance · to −18 °FAlaska oniongrass3 ft · blooms mid spring · low shade tolerance · to −33 °FAlpine Meadow-Foxtail0.5 ft · blooms mid spring · medium shade tolerance · to −33 °Falpine timothy1.4 ft · blooms late spring · medium shade tolerance · to −43 °Farctic bluegrass2 ft · high shade tolerance · to −62 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °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 Yakutat, AK.

Soil in Yakutat, AK

The soil mapped at the center of ZIP 99689 is Terric Cryohemists — peat, very poorly drained.

TexturePeattop layer
pH4.5strongly acidic; most vegetables like 6.0–7.0
DrainageVery poorly drainedconsider raised beds
Organic matter75%high
Hydrologic groupB/Dmoderate when drained; wet otherwise
Farmland classNot prime farmlandUSDA classification

Map unit: Terric Cryohemists-Histic Cryaquepts complex, flat lowlands, 0 to 5 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 99689; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Yakutat, AK

Summer high62 °Faverage high, July
Winter low22 °Faverage low, January
Hot days0days a year at 90 °F or more
Freezing nights157nights a year at 32 °F or less
Growing degree days448base 50 °F — the season’s usable heat
Longest day18 h 41 mindaylight on June 21
Shortest day6 h 02 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation140.4 inper year, rain and melted snow
Snowfall147 inper year; 122 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°32 °FJanuary: average high 35 °F, low 22 °F 35°22° JanFebruary: average high 38 °F, low 24 °F 38°24° FebMarch: average high 40 °F, low 24 °F 40°24° MarApril: average high 47 °F, low 30 °F 47°30° AprMay: average high 54 °F, low 38 °F 54°38° MayJune: average high 59 °F, low 45 °F 59°45° JunJuly: average high 62 °F, low 49 °F 62°49° JulAugust: average high 62 °F, low 48 °F 62°48° AugSeptember: average high 57 °F, low 42 °F 57°42° SepOctober: average high 49 °F, low 35 °F 49°35° OctNovember: average high 40 °F, low 27 °F 40°27° NovDecember: average high 36 °F, low 25 °F 36°25° Dec

Precipitation by month inches · ❄ = snowfall

0″2″4″6″8″10″12″14″16″18″20″January: 12.41 in precipitation, 28.9 in snowfall 12.4❄29 JanFebruary: 10.29 in precipitation, 27.5 in snowfall 10.3❄28 FebMarch: 9.52 in precipitation, 30.4 in snowfall 9.5❄30 MarApril: 7.94 in precipitation, 7.2 in snowfall 7.9❄7 AprMay: 7.85 in precipitation, 0.3 in snowfall 7.8 MayJune: 5.41 in precipitation 5.4 JunJuly: 7.63 in precipitation 7.6 JulAugust: 13.91 in precipitation 13.9 AugSeptember: 19.03 in precipitation 19.0 SepOctober: 18.88 in precipitation, 3.4 in snowfall 18.9❄3 OctNovember: 13.55 in precipitation, 20 in snowfall 13.6❄20 NovDecember: 13.94 in precipitation, 29.6 in snowfall 13.9❄30 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Yakutat State Airport, AK (9 mi away); precipitation: Yakutat State Airport, AK (9 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 0 nearest ZIP codes share zone 6b.

Alaska planting zones →

Questions about 99689

What planting zone is ZIP code 99689?

ZIP code 99689 (Yakutat, AK) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Yakutat, AK?

The median last spring frost (32 °F) near 99689 is May 20; after May 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Yakutat State Airport station.

When is the first frost in Yakutat, AK?

The median first fall frost near 99689 is September 23, giving a median frost-free growing season of 124 days.

When should I plant tomatoes in 99689?

Start tomato seeds indoors around Mar 25 – Apr 8 and set transplants outside around May 27 – Jun 10, one to three weeks after the median last frost.

How much rain and snow does 99689 get?

About 140.4 inches of precipitation a year and 147 inches of snowfall (NOAA 1991–2020 normals, Yakutat State Airport station).

How hot do summers get in Yakutat, AK?

The average high peaks at 62 °F in July, with about 0 days a year at 90 °F or more.

What kind of soil does 99689 have?

The USDA soil survey maps Terric Cryohemists at the center of ZIP 99689: peat, very poorly drained, pH about 4.5 (strongly acidic).

What kind of onions grow in Yakutat, AK?

Long-day onions: the longest day near 99689 is 18 h 41 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).