Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 83839 — Kingston, ID

ZIP code 83839 (Kingston, Shoshone County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is May 14 and the first fall frost September 26.

Where ZIP 83839 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 14

First frostSep 26

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 Kingston, 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 Kingston, ID

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 14median — 50% chance of a later frost

Safe for tender plantsJune 3only 10% chance of frost after

First fall frostSeptember 26median — 10% chance by Sep 9

Growing season131 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 30 and returns around October 8.

From the NOAA station Kellogg, ID — 7 miles away, elevation 2,379 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 83839

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 2 – Apr 16

SpinachSow outdoors · Apr 2 – Apr 23

Broccoli, cabbageStart indoors · Mar 5 – Mar 19

Broccoli, cabbageTransplant · Apr 23 – May 7

Onion setsPlant outdoors · Apr 16 – Apr 30

PotatoesPlant outdoors · Apr 23 – May 7

LettuceSow outdoors · Apr 16 – Apr 30

Carrots, beetsSow outdoors · Apr 23 – May 7

TomatoesStart indoors · Mar 19 – Apr 2

TomatoesTransplant · May 21 – Jun 4

Peppers, eggplantStart indoors · Mar 5 – Mar 19

Peppers, eggplantTransplant · May 28 – Jun 11

BeansSow outdoors · May 21 – Jun 4

Sweet cornSow outdoors · May 21 – Jun 4

Cucumbers, squashSow outdoors · May 21 – Jun 4

Fall lettuce, spinachSow outdoors · Aug 1 – Aug 15

GarlicPlant cloves · Sep 12 – Oct 17

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 14) and first fall frost (Sep 26) 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 83839 came on Apr 12 — 8 days earlier than the 1991–2020 average (Apr 20).

average
Apr 202026
Apr 12

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).

Soil in Kingston, ID

The soil mapped at the center of ZIP 83839 is Honeyjones — moderately decomposed plant material, well drained.

TextureModerately decomposed plant materialtop layer

pH5.0strongly acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter75%high

Hydrologic groupBwater soaks in moderately

Farmland classNot prime farmlandUSDA classification

Map unit: Honeyjones-Ahrs association, very rocky, 35 to 75 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 83839; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Kingston, ID

Summer high85 °Faverage high, July

Winter low22 °Faverage low, January

Hot days21days a year at 90 °F or more

Freezing nights147nights a year at 32 °F or less

Growing degree days1,843base 50 °F — the season’s usable heat

Longest day15 h 59 mindaylight on June 21

Shortest day8 h 25 mindaylight on December 21

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

Precipitation33.7 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: Kellogg, ID (7 mi away); precipitation: Kellogg 0.6 Ene, ID (6 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

838686b

Smelterville, ID · 7 mi

Pinehurst, ID · 12 mi

838676b

Silverton, ID · 14 mi

Idaho planting zones →

Questions about 83839

What planting zone is ZIP code 83839?

ZIP code 83839 (Kingston, ID) 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 Kingston, ID?

The median last spring frost (32 °F) near 83839 is May 14; after June 3 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Kellogg station.

When is the first frost in Kingston, ID?

The median first fall frost near 83839 is September 26, giving a median frost-free growing season of 131 days.

When should I plant tomatoes in 83839?

Start tomato seeds indoors around Mar 19 – Apr 2 and set transplants outside around May 21 – Jun 4, one to three weeks after the median last frost.

How much rain and snow does 83839 get?

About 33.7 inches of precipitation a year (NOAA 1991–2020 normals, Kellogg 0.6 Ene station).

How hot do summers get in Kingston, ID?

The average high peaks at 85 °F in July, with about 21 days a year at 90 °F or more.

What kind of soil does 83839 have?

The USDA soil survey maps Honeyjones at the center of ZIP 83839: moderately decomposed plant material, well drained, pH about 5.0 (strongly acidic).

Did spring come early in Kingston, ID in 2026?

Spring leaf-out near 83839 came on Apr 12 in 2026, 8 days earlier than the 1991–2020 average (Apr 20), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Kingston, ID?

Long-day onions: the longest day near 83839 is 15 h 59 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).