Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 30, 2026

Planting zone for 83276 — Soda Springs, ID

ZIP code 83276 (Soda Springs, Caribou County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is May 29 and the first fall frost September 17.

Where ZIP 83276 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.

Zone5a−20 to −15 °F

Coldest night−28.9 to −26.1 °C

Last frostMay 29

First frostSep 17

2012 zone4b

Was 4b 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 5a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Soda Springs, ID…

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 Soda Springs, ID

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostMay 29median — 50% chance of a later frost

Safe for tender plantsJune 16only 10% chance of frost after

First fall frostSeptember 17median — 10% chance by Sep 1

Growing season111 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 9 and returns around October 1.

From the NOAA station Grace, ID — 19 miles away, elevation 5,551 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 83276

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 17 – May 1

SpinachSow outdoors · Apr 17 – May 8

Broccoli, cabbageStart indoors · Mar 20 – Apr 3

Broccoli, cabbageTransplant · May 8 – May 22

Onion setsPlant outdoors · May 1 – May 15

PotatoesPlant outdoors · May 8 – May 22

LettuceSow outdoors · May 1 – May 15

Carrots, beetsSow outdoors · May 8 – May 22

TomatoesStart indoors · Apr 3 – Apr 17

TomatoesTransplant · Jun 5 – Jun 19

Peppers, eggplantStart indoors · Mar 20 – Apr 3

Peppers, eggplantTransplant · Jun 12 – Jun 26

BeansSow outdoors · Jun 5 – Jun 19

Sweet cornSow outdoors · Jun 5 – Jun 19

Cucumbers, squashSow outdoors · Jun 5 – Jun 19

Fall lettuce, spinachSow outdoors · Jul 23 – Aug 6

GarlicPlant cloves · Sep 3 – Oct 8

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 29) and first fall frost (Sep 17) 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.

When spring arrived in 2026

In 2026, spring leaf-out near 83276 came on Apr 8 — 25 days earlier than the 1991–2020 average (May 3).

average
May 32026
Apr 8

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 5a in Idaho

536 plants native to the lower 48 states, recorded in Idaho, and rated by the USDA to survive −20 °F or colder — the bottom of zone 5a. Each links to its USDA PLANTS profile.

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 Soda Springs, ID.

Soil in Soda Springs, ID

The soil mapped at the center of ZIP 83276 is Ireland — gravelly loam, well drained.

TextureGravelly loama good balance for most vegetables

pH7.2neutral; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2%moderate

Hydrologic groupCwater soaks in slowly

Farmland classNot prime farmlandUSDA classification

Map unit: Ireland-Ricrest-Lanoak complex, 12 to 40 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 83276; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Soda Springs, ID

Summer high87 °Faverage high, July

Winter low10 °Faverage low, January

Hot days15days a year at 90 °F or more

Freezing nights228nights a year at 32 °F or less

Growing degree days1,548base 50 °F — the season’s usable heat

Longest day15 h 20 mindaylight on June 21

Shortest day9 h 02 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation18.8 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Soda Springs Airport, ID (11 mi away); precipitation: Soda Springs 0.3 W, ID (11 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.

832395b

Georgetown, ID · 16 mi

Idaho planting zones →

Questions about 83276

What planting zone is ZIP code 83276?

ZIP code 83276 (Soda Springs, ID) is in USDA hardiness zone 5a on the 2023 map: the coldest night of an average winter reaches −20 to −15 °F (−28.9 to −26.1 °C).

When is the last frost in Soda Springs, ID?

The median last spring frost (32 °F) near 83276 is May 29; after June 16 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Grace station.

When is the first frost in Soda Springs, ID?

The median first fall frost near 83276 is September 17, giving a median frost-free growing season of 111 days.

When should I plant tomatoes in 83276?

Start tomato seeds indoors around Apr 3 – Apr 17 and set transplants outside around Jun 5 – Jun 19, one to three weeks after the median last frost.

How much rain and snow does 83276 get?

About 18.8 inches of precipitation a year (NOAA 1991–2020 normals, Soda Springs 0.3 W station).

How hot do summers get in Soda Springs, ID?

The average high peaks at 87 °F in July, with about 15 days a year at 90 °F or more.

What kind of soil does 83276 have?

The USDA soil survey maps Ireland at the center of ZIP 83276: gravelly loam, well drained, pH about 7.2 (neutral).

Did spring come early in Soda Springs, ID in 2026?

Spring leaf-out near 83276 came on Apr 8 in 2026, 25 days earlier than the 1991–2020 average (May 3), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Soda Springs, ID?

Long-day onions: the longest day near 83276 is 15 h 20 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 83276 change?

Yes. The 2012 USDA map put 83276 in zone 4b; the 2023 map puts it in zone 5a. The newer map uses 1991–2020 data and more weather stations.