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

Planting zone for 97040 — Mosier, OR

ZIP code 97040 (Mosier, Wasco County) is in USDA zone 7b: the coldest winter night averages 5 to 10 °F. The median last spring frost is April 20 and the first fall frost October 13.

Where ZIP 97040 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.

Zone7b5 to 10 °F
Coldest night−15 to −12.2 °C
Last frostApr 20
First frostOct 13
2012 zone7b

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 7b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Mosier, 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 Mosier, OR

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 20median — 50% chance of a later frost
Safe for tender plantsMay 9only 10% chance of frost after
First fall frostOctober 13median — 10% chance by Sep 30
Growing season177 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 20 and returns around October 28.

From the NOAA station Hood Rvr Exp Stn, OR — 8 miles away, elevation 499 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 97040

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 9 – Mar 23
SpinachSow outdoors · Mar 9 – Mar 30
Broccoli, cabbageStart indoors · Feb 9 – Feb 23
Broccoli, cabbageTransplant · Mar 30 – Apr 13
Onion setsPlant outdoors · Mar 23 – Apr 6
PotatoesPlant outdoors · Mar 30 – Apr 13
LettuceSow outdoors · Mar 23 – Apr 6
Carrots, beetsSow outdoors · Mar 30 – Apr 13
TomatoesStart indoors · Feb 23 – Mar 9
TomatoesTransplant · Apr 27 – May 11
Peppers, eggplantStart indoors · Feb 9 – Feb 23
Peppers, eggplantTransplant · May 4 – May 18
BeansSow outdoors · Apr 27 – May 11
Sweet cornSow outdoors · Apr 27 – May 11
Cucumbers, squashSow outdoors · Apr 27 – May 11
Fall lettuce, spinachSow outdoors · Aug 18 – Sep 1
GarlicPlant cloves · Sep 29 – Nov 3
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 20) and first fall frost (Oct 13) 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 97040 came on Mar 8 — 10 days earlier than the 1991–2020 average (Mar 18).

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 Mosier, OR

The soil mapped at the center of ZIP 97040 is Ketchly — slightly decomposed plant material, well drained.

TextureSlightly decomposed plant materialtop layer
pH5.0strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter75%high
Hydrologic groupCwater soaks in slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Ketchly loam, 3 to 30 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 97040; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Mosier, OR

Summer high82 °Faverage high, July
Winter low30 °Faverage low, January
Hot days21days a year at 90 °F or more
Freezing nights92nights a year at 32 °F or less
Growing degree days2,282base 50 °F — the season’s usable heat
Longest day15 h 42 mindaylight on June 21
Shortest day8 h 41 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation30.4 inper year, rain and melted snow
Snowfall17 inper year; 12 days with snow on the ground

Average high and low, by month

20°30°40°50°60°70°80°90°32 °FJanuary: average high 41 °F, low 30 °F 41°30° JanFebruary: average high 46 °F, low 31 °F 46°31° FebMarch: average high 53 °F, low 35 °F 53°35° MarApril: average high 60 °F, low 39 °F 60°39° AprMay: average high 68 °F, low 46 °F 68°46° MayJune: average high 74 °F, low 51 °F 74°51° JunJuly: average high 82 °F, low 56 °F 82°56° JulAugust: average high 82 °F, low 55 °F 82°55° AugSeptember: average high 76 °F, low 47 °F 76°47° SepOctober: average high 63 °F, low 39 °F 63°39° OctNovember: average high 49 °F, low 34 °F 49°34° NovDecember: average high 40 °F, low 31 °F 40°31° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″6″January: 5.23 in precipitation, 6.9 in snowfall 5.2❄7 JanFebruary: 3.51 in precipitation, 2.5 in snowfall 3.5❄3 FebMarch: 3.18 in precipitation, 0.7 in snowfall 3.2❄1 MarApril: 1.84 in precipitation 1.8 AprMay: 1.32 in precipitation 1.3 MayJune: 0.82 in precipitation 0.8 JunJuly: 0.24 in precipitation 0.2 JulAugust: 0.24 in precipitation 0.2 AugSeptember: 0.71 in precipitation 0.7 SepOctober: 2.64 in precipitation, 0.1 in snowfall 2.6 OctNovember: 4.83 in precipitation, 1.5 in snowfall 4.8❄2 NovDecember: 5.86 in precipitation, 5.5 in snowfall 5.9❄6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Hood Rvr Exp Stn, OR (8 mi away); precipitation: Hood Rvr Exp Stn, OR (8 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

970317b
Hood River, OR · 10 mi
970587b
The Dalles, OR · 12 mi
986178a
Dallesport, WA · 12 mi
986518a
Underwood, WA · 13 mi
986357b
Lyle, WA · 13 mi
986238a
Husum, WA · 14 mi
986727b
White Salmon, WA · 15 mi
970417b
Mount Hood Parkdale, OR · 17 mi

Oregon planting zones →

Questions about 97040

What planting zone is ZIP code 97040?

ZIP code 97040 (Mosier, OR) is in USDA hardiness zone 7b on the 2023 map: the coldest night of an average winter reaches 5 to 10 °F (−15 to −12.2 °C).

When is the last frost in Mosier, OR?

The median last spring frost (32 °F) near 97040 is April 20; after May 9 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Hood Rvr Exp Stn station.

When is the first frost in Mosier, OR?

The median first fall frost near 97040 is October 13, giving a median frost-free growing season of 177 days.

When should I plant tomatoes in 97040?

Start tomato seeds indoors around Feb 23 – Mar 9 and set transplants outside around Apr 27 – May 11, one to three weeks after the median last frost.

How much rain and snow does 97040 get?

About 30.4 inches of precipitation a year and 17 inches of snowfall (NOAA 1991–2020 normals, Hood Rvr Exp Stn station).

How hot do summers get in Mosier, OR?

The average high peaks at 82 °F in July, with about 21 days a year at 90 °F or more.

What kind of soil does 97040 have?

The USDA soil survey maps Ketchly at the center of ZIP 97040: slightly decomposed plant material, well drained, pH about 5.0 (strongly acidic).

Did spring come early in Mosier, OR in 2026?

Spring leaf-out near 97040 came on Mar 8 in 2026, 10 days earlier than the 1991–2020 average (Mar 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Mosier, OR?

Long-day onions: the longest day near 97040 is 15 h 42 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).