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

Planting zone for 89421 — Mc Dermitt, NV

ZIP code 89421 (Mc Dermitt, Humboldt County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is May 28 and the first fall frost September 23.

Where ZIP 89421 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.

Zone7a0 to 5 °F

Coldest night−17.8 to −15 °C

Last frostMay 28

First frostSep 23

2012 zone6a

Was 6a on the 2012 map — a full zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Mc Dermitt, NV…

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 Mc Dermitt, NV

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 28median — 50% chance of a later frost

Safe for tender plantsJune 15only 10% chance of frost after

First fall frostSeptember 23median — 10% chance by Sep 7

Growing season117 daysfrost-free, median

A hard freeze (28 °F) usually ends around May 7 and returns around October 4.

From the NOAA station Kings Rvr Vly - Orovada 26nw, NV — 25 miles away, elevation 4,239 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 89421

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Apr 16 – Apr 30

SpinachSow outdoors · Apr 16 – May 7

Broccoli, cabbageStart indoors · Mar 19 – Apr 2

Broccoli, cabbageTransplant · May 7 – May 21

Onion setsPlant outdoors · Apr 30 – May 14

PotatoesPlant outdoors · May 7 – May 21

LettuceSow outdoors · Apr 30 – May 14

Carrots, beetsSow outdoors · May 7 – May 21

TomatoesStart indoors · Apr 2 – Apr 16

TomatoesTransplant · Jun 4 – Jun 18

Peppers, eggplantStart indoors · Mar 19 – Apr 2

Peppers, eggplantTransplant · Jun 11 – Jun 25

BeansSow outdoors · Jun 4 – Jun 18

Sweet cornSow outdoors · Jun 4 – Jun 18

Cucumbers, squashSow outdoors · Jun 4 – Jun 18

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 28) 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.

When spring arrived in 2026

In 2026, spring leaf-out near 89421 came on Mar 6 — 23 days earlier than the 1991–2020 average (Mar 29).

average
Mar 292026
Mar 6

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 7a in Nevada

520 plants native to the lower 48 states, recorded in Nevada, and rated by the USDA to survive 0 °F or colder — the bottom of zone 7a. 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 Mc Dermitt, NV.

Soil in Mc Dermitt, NV

The soil mapped at the center of ZIP 89421 is Wieland — ashy silt loam, well drained.

TextureAshy silt loama good balance for most vegetables

pH7.8slightly alkaline; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter1.5%low — add compost

Hydrologic groupDwater soaks in very slowly

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Wieland silt loam, 4 to 8 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 89421; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mc Dermitt, NV

Summer high92 °Faverage high, July

Winter low16 °Faverage low, December

Hot days48days a year at 90 °F or more

Freezing nights196nights a year at 32 °F or less

Growing degree days2,087base 50 °F — the season’s usable heat

Longest day15 h 15 mindaylight on June 21

Shortest day9 h 06 mindaylight on December 21

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

Precipitation7.8 inper year, rain and melted snow

Snowfall21 inper year; 20 days with snow on the ground

Average high and low, by month

Precipitation by month inches · ❄ = snowfall

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Mcdermitt, NV (12 mi away); precipitation: Mcdermitt, NV (12 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

Princeton, OR · 42 mi

894266a

Paradise Valley, NV · 43 mi

894046b

Denio, NV · 50 mi

979106b

Jordan Valley, OR · 60 mi

894456b

Winnemucca, NV · 64 mi

979026b

Arock, OR · 64 mi

Nevada planting zones →

Questions about 89421

What planting zone is ZIP code 89421?

ZIP code 89421 (Mc Dermitt, NV) is in USDA hardiness zone 7a on the 2023 map: the coldest night of an average winter reaches 0 to 5 °F (−17.8 to −15 °C).

When is the last frost in Mc Dermitt, NV?

The median last spring frost (32 °F) near 89421 is May 28; after June 15 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Kings Rvr Vly - Orovada 26nw station.

When is the first frost in Mc Dermitt, NV?

The median first fall frost near 89421 is September 23, giving a median frost-free growing season of 117 days.

When should I plant tomatoes in 89421?

Start tomato seeds indoors around Apr 2 – Apr 16 and set transplants outside around Jun 4 – Jun 18, one to three weeks after the median last frost.

How much rain and snow does 89421 get?

About 7.8 inches of precipitation a year and 21 inches of snowfall (NOAA 1991–2020 normals, Mcdermitt station).

How hot do summers get in Mc Dermitt, NV?

The average high peaks at 92 °F in July, with about 48 days a year at 90 °F or more.

What kind of soil does 89421 have?

The USDA soil survey maps Wieland at the center of ZIP 89421: ashy silt loam, well drained, pH about 7.8 (slightly alkaline).

Did spring come early in Mc Dermitt, NV in 2026?

Spring leaf-out near 89421 came on Mar 6 in 2026, 23 days earlier than the 1991–2020 average (Mar 29), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mc Dermitt, NV?

Long-day onions: the longest day near 89421 is 15 h 15 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 89421 change?

Yes. The 2012 USDA map put 89421 in zone 6a; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.