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

Planting zone for 87730 — Mills, NM

ZIP code 87730 (Mills, Harding County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is April 30 and the first fall frost October 15.

Where ZIP 87730 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 frostApr 30

First frostOct 15

2012 zone6a

Was 6a 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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Mills, NM…

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 Mills, NM

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 30median — 50% chance of a later frost

Safe for tender plantsMay 11only 10% chance of frost after

First fall frostOctober 15median — 10% chance by Oct 3

Growing season167 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 21 and returns around October 23.

From the NOAA station Roy, NM — 13 miles away, elevation 5,745 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 87730

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 19 – Apr 2

SpinachSow outdoors · Mar 19 – Apr 9

Broccoli, cabbageStart indoors · Feb 19 – Mar 5

Broccoli, cabbageTransplant · Apr 9 – Apr 23

Onion setsPlant outdoors · Apr 2 – Apr 16

PotatoesPlant outdoors · Apr 9 – Apr 23

LettuceSow outdoors · Apr 2 – Apr 16

Carrots, beetsSow outdoors · Apr 9 – Apr 23

TomatoesStart indoors · Mar 5 – Mar 19

TomatoesTransplant · May 7 – May 21

Peppers, eggplantStart indoors · Feb 19 – Mar 5

Peppers, eggplantTransplant · May 14 – May 28

BeansSow outdoors · May 7 – May 21

Sweet cornSow outdoors · May 7 – May 21

Cucumbers, squashSow outdoors · May 7 – May 21

Fall lettuce, spinachSow outdoors · Aug 20 – Sep 3

GarlicPlant cloves · Oct 1 – Nov 5

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 30) and first fall frost (Oct 15) 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 87730 came on Feb 28 — 18 days earlier than the 1991–2020 average (Mar 18).

average
Mar 182026
Feb 28

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 6b in New Mexico

515 plants native to the lower 48 states, recorded in New Mexico, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. 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 Mills, NM.

Soil in Mills, NM

The soil mapped at the center of ZIP 87730 is Tricon — clay loam, well drained.

TextureClay loamholds water and nutrients; slow to drain and warm up

pH7.2neutral; 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: Tricon complex.

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 87730; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mills, NM

Summer high88 °Faverage high, July

Winter low21 °Faverage low, January

Hot days24days a year at 90 °F or more

Freezing nights136nights a year at 32 °F or less

Growing degree days3,043base 50 °F — the season’s usable heat

Longest day14 h 37 mindaylight on June 21

Shortest day9 h 42 mindaylight on December 21

Onions to growIntermediateday-neutral types bulb best; long-day varieties may not bulb fully

Precipitation16.4 inper year, rain and melted snow

Snowfall19 inper year; 12 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: Roy, NM (13 mi away); precipitation: Roy, NM (13 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

Gladstone, NM · 21 mi

877526a

Wagon Mound, NM · 25 mi

Grenville, NM · 39 mi

New Mexico planting zones →

Questions about 87730

What planting zone is ZIP code 87730?

ZIP code 87730 (Mills, NM) 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 Mills, NM?

The median last spring frost (32 °F) near 87730 is April 30; after May 11 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Roy station.

When is the first frost in Mills, NM?

The median first fall frost near 87730 is October 15, giving a median frost-free growing season of 167 days.

When should I plant tomatoes in 87730?

Start tomato seeds indoors around Mar 5 – Mar 19 and set transplants outside around May 7 – May 21, one to three weeks after the median last frost.

How much rain and snow does 87730 get?

About 16.4 inches of precipitation a year and 19 inches of snowfall (NOAA 1991–2020 normals, Roy station).

How hot do summers get in Mills, NM?

The average high peaks at 88 °F in July, with about 24 days a year at 90 °F or more.

What kind of soil does 87730 have?

The USDA soil survey maps Tricon at the center of ZIP 87730: clay loam, well drained, pH about 7.2 (neutral).

Did spring come early in Mills, NM in 2026?

Spring leaf-out near 87730 came on Feb 28 in 2026, 18 days earlier than the 1991–2020 average (Mar 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mills, NM?

Intermediate onions: the longest day near 87730 is 14 h 37 min, so day-neutral types bulb best; long-day varieties may not bulb fully.

Did the zone for 87730 change?

Yes. The 2012 USDA map put 87730 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.