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

Planting zone for 97039 — Moro, OR

ZIP code 97039 (Moro, Sherman County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is May 12 and the first fall frost October 4.

Where ZIP 97039 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 12

First frostOct 4

2012 zone6b

Was 6b 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 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Moro, OR…

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 Moro, OR

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostMay 12median — 50% chance of a later frost

Safe for tender plantsMay 31only 10% chance of frost after

First fall frostOctober 4median — 10% chance by Sep 16

Growing season143 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 26 and returns around October 16.

From the NOAA station Moro, OR — 5 miles away, elevation 1,870 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 97039

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 31 – Apr 14

SpinachSow outdoors · Mar 31 – Apr 21

Broccoli, cabbageStart indoors · Mar 3 – Mar 17

Broccoli, cabbageTransplant · Apr 21 – May 5

Onion setsPlant outdoors · Apr 14 – Apr 28

PotatoesPlant outdoors · Apr 21 – May 5

LettuceSow outdoors · Apr 14 – Apr 28

Carrots, beetsSow outdoors · Apr 21 – May 5

TomatoesStart indoors · Mar 17 – Mar 31

TomatoesTransplant · May 19 – Jun 2

Peppers, eggplantStart indoors · Mar 3 – Mar 17

Peppers, eggplantTransplant · May 26 – Jun 9

BeansSow outdoors · May 19 – Jun 2

Sweet cornSow outdoors · May 19 – Jun 2

Cucumbers, squashSow outdoors · May 19 – Jun 2

Fall lettuce, spinachSow outdoors · Aug 9 – Aug 23

GarlicPlant cloves · Sep 20 – Oct 25

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 12) and first fall frost (Oct 4) 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 97039 came on Mar 17 — 5 days earlier than the 1991–2020 average (Mar 22).

average
Mar 222026
Mar 17

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 Oregon

624 plants native to the lower 48 states, recorded in Oregon, 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 Moro, OR.

Soil in Moro, OR

The soil mapped at the center of ZIP 97039 is Walla Walla — silt loam, well drained.

TextureSilt loama good balance for most vegetables

pH7.2neutral; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter2.5%moderate

Hydrologic groupBwater soaks in moderately

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Walla Walla silt loam, 7 to 15 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 97039; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Moro, OR

Summer high84 °Faverage high, July

Winter low24 °Faverage low, December

Hot days22days a year at 90 °F or more

Freezing nights126nights a year at 32 °F or less

Growing degree days2,088base 50 °F — the season’s usable heat

Longest day15 h 41 mindaylight on June 21

Shortest day8 h 42 mindaylight on December 21

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

Precipitation11 inper year, rain and melted snow

Snowfall17 inper year; 24 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: Moro, OR (5 mi away); precipitation: Moro, OR (5 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.

970657b

Wasco, OR · 10 mi

970297a

Grass Valley, OR · 15 mi

Arlington, OR · 19 mi

Oregon planting zones →

Questions about 97039

What planting zone is ZIP code 97039?

ZIP code 97039 (Moro, OR) 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 Moro, OR?

The median last spring frost (32 °F) near 97039 is May 12; after May 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Moro station.

When is the first frost in Moro, OR?

The median first fall frost near 97039 is October 4, giving a median frost-free growing season of 143 days.

When should I plant tomatoes in 97039?

Start tomato seeds indoors around Mar 17 – Mar 31 and set transplants outside around May 19 – Jun 2, one to three weeks after the median last frost.

How much rain and snow does 97039 get?

About 11 inches of precipitation a year and 17 inches of snowfall (NOAA 1991–2020 normals, Moro station).

How hot do summers get in Moro, OR?

The average high peaks at 84 °F in July, with about 22 days a year at 90 °F or more.

What kind of soil does 97039 have?

The USDA soil survey maps Walla Walla at the center of ZIP 97039: silt loam, well drained, pH about 7.2 (neutral).

Did spring come early in Moro, OR in 2026?

Spring leaf-out near 97039 came on Mar 17 in 2026, 5 days earlier than the 1991–2020 average (Mar 22), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Moro, OR?

Long-day onions: the longest day near 97039 is 15 h 41 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 97039 change?

Yes. The 2012 USDA map put 97039 in zone 6b; the 2023 map puts it in zone 7a. The newer map uses 1991–2020 data and more weather stations.