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

Planting zone for 83235 — Ellis, ID

ZIP code 83235 (Ellis, Custer County) is in USDA zone 5b: the coldest winter night averages −15 to −10 °F. The median last spring frost is June 12 and the first fall frost September 6.

Where ZIP 83235 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.

Zone5b−15 to −10 °F
Coldest night−26.1 to −23.3 °C
Last frostJun 12
First frostSep 6
2012 zone5a

Was 5a 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 5b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Ellis, 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 Ellis, ID

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostJune 12median — 50% chance of a later frost
Safe for tender plantsJune 29only 10% chance of frost after
First fall frostSeptember 6median — 10% chance by Aug 23
Growing season85 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 20 and returns around September 19.

From the NOAA station May 2sse, ID — 9 miles away, elevation 5,049 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 83235

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · May 1 – May 15
SpinachSow outdoors · May 1 – May 22
Broccoli, cabbageStart indoors · Apr 3 – Apr 17
Broccoli, cabbageTransplant · May 22 – Jun 5
Onion setsPlant outdoors · May 15 – May 29
PotatoesPlant outdoors · May 22 – Jun 5
LettuceSow outdoors · May 15 – May 29
Carrots, beetsSow outdoors · May 22 – Jun 5
TomatoesStart indoors · Apr 17 – May 1
TomatoesTransplant · Jun 19 – Jul 3
Peppers, eggplantStart indoors · Apr 3 – Apr 17
Peppers, eggplantTransplant · Jun 26 – Jul 10
BeansSow outdoors · Jun 19 – Jul 3
Sweet cornSow outdoors · Jun 19 – Jul 3
Cucumbers, squashSow outdoors · Jun 19 – Jul 3
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 (Jun 12) 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.

When spring arrived in 2026

In 2026, spring leaf-out near 83235 came on Apr 6 — 14 days earlier than the 1991–2020 average (Apr 20).

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 5b in Idaho

553 plants native to the lower 48 states, recorded in Idaho, and rated by the USDA to survive −15 °F or colder — the bottom of zone 5b. Each links to its USDA PLANTS profile.

Trees 30

Shrubs 94

Wildflowers & perennials 267

Grasses 151

Vines 1

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 Ellis, ID.

Soil in Ellis, ID

The soil mapped at the center of ZIP 83235 is Dacont — gravelly loam, well drained.

TextureGravelly loama good balance for most vegetables
pH7.0neutral; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter1.5%low — add compost
Hydrologic groupBwater soaks in moderately
Farmland classNot prime farmlandUSDA classification

Map unit: Dacont-Custco association, 20 to 50 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 83235; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Ellis, ID

Summer high87 °Faverage high, July
Winter low6 °Faverage low, January
Hot days25days a year at 90 °F or more
Freezing nights220nights a year at 32 °F or less
Growing degree days1,533base 50 °F — the season’s usable heat
Longest day15 h 34 mindaylight on June 21
Shortest day8 h 49 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation8.5 inper year, rain and melted snow

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 32 °F, low 6 °F 32°6° JanFebruary: average high 39 °F, low 13 °F 39°13° FebMarch: average high 51 °F, low 19 °F 51°19° MarApril: average high 58 °F, low 25 °F 58°25° AprMay: average high 68 °F, low 34 °F 68°34° MayJune: average high 76 °F, low 41 °F 76°41° JunJuly: average high 87 °F, low 45 °F 87°45° JulAugust: average high 85 °F, low 42 °F 85°42° AugSeptember: average high 76 °F, low 35 °F 76°35° SepOctober: average high 60 °F, low 25 °F 60°25° OctNovember: average high 44 °F, low 17 °F 44°17° NovDecember: average high 32 °F, low 9 °F 32°9° Dec

Precipitation by month inches

0″1″2″January: 0.32 in precipitation 0.3 JanFebruary: 0.26 in precipitation 0.3 FebMarch: 0.66 in precipitation 0.7 MarApril: 0.81 in precipitation 0.8 AprMay: 1.22 in precipitation 1.2 MayJune: 1.28 in precipitation 1.3 JunJuly: 0.45 in precipitation 0.5 JulAugust: 0.88 in precipitation 0.9 AugSeptember: 0.89 in precipitation 0.9 SepOctober: 0.93 in precipitation 0.9 OctNovember: 0.48 in precipitation 0.5 NovDecember: 0.32 in precipitation 0.3 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: May 2sse, ID (9 mi away); precipitation: May 2sse, ID (9 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.

Idaho planting zones →

Questions about 83235

What planting zone is ZIP code 83235?

ZIP code 83235 (Ellis, ID) is in USDA hardiness zone 5b on the 2023 map: the coldest night of an average winter reaches −15 to −10 °F (−26.1 to −23.3 °C).

When is the last frost in Ellis, ID?

The median last spring frost (32 °F) near 83235 is June 12; after June 29 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, May 2sse station.

When is the first frost in Ellis, ID?

The median first fall frost near 83235 is September 6, giving a median frost-free growing season of 85 days.

When should I plant tomatoes in 83235?

Start tomato seeds indoors around Apr 17 – May 1 and set transplants outside around Jun 19 – Jul 3, one to three weeks after the median last frost.

How much rain and snow does 83235 get?

About 8.5 inches of precipitation a year (NOAA 1991–2020 normals, May 2sse station).

How hot do summers get in Ellis, ID?

The average high peaks at 87 °F in July, with about 25 days a year at 90 °F or more.

What kind of soil does 83235 have?

The USDA soil survey maps Dacont at the center of ZIP 83235: gravelly loam, well drained, pH about 7.0 (neutral).

Did spring come early in Ellis, ID in 2026?

Spring leaf-out near 83235 came on Apr 6 in 2026, 14 days earlier than the 1991–2020 average (Apr 20), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Ellis, ID?

Long-day onions: the longest day near 83235 is 15 h 34 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 83235 change?

Yes. The 2012 USDA map put 83235 in zone 5a; the 2023 map puts it in zone 5b. The newer map uses 1991–2020 data and more weather stations.