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

Planting zone for 97148 — Yamhill, OR

ZIP code 97148 (Yamhill, Yamhill County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is April 5 and the first fall frost November 7.

Where ZIP 97148 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.

Zone8b15 to 20 °F

Coldest night−9.4 to −6.7 °C

Last frostApr 5

First frostNov 7

2012 zone8b

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 8b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Yamhill, 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 Yamhill, OR

JanFebMarAprMayJunJulAugSepOctNovDec

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

Last spring frostApril 5median — 50% chance of a later frost

Safe for tender plantsApril 27only 10% chance of frost after

First fall frostNovember 7median — 10% chance by Oct 20

Growing season216 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 20 and returns around November 28.

From the NOAA station Mc Minnville, OR — 11 miles away, elevation 154 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 97148

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 22 – Mar 8

SpinachSow outdoors · Feb 22 – Mar 15

Broccoli, cabbageStart indoors · Jan 25 – Feb 8

Broccoli, cabbageTransplant · Mar 15 – Mar 29

Onion setsPlant outdoors · Mar 8 – Mar 22

PotatoesPlant outdoors · Mar 15 – Mar 29

LettuceSow outdoors · Mar 8 – Mar 22

Carrots, beetsSow outdoors · Mar 15 – Mar 29

TomatoesStart indoors · Feb 8 – Feb 22

TomatoesTransplant · Apr 12 – Apr 26

Peppers, eggplantStart indoors · Jan 25 – Feb 8

Peppers, eggplantTransplant · Apr 19 – May 3

BeansSow outdoors · Apr 12 – Apr 26

Sweet cornSow outdoors · Apr 12 – Apr 26

Cucumbers, squashSow outdoors · Apr 12 – Apr 26

Fall lettuce, spinachSow outdoors · Sep 12 – Sep 26

GarlicPlant cloves · Oct 24 – Nov 28

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 5) and first fall frost (Nov 7) 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 97148 came on Feb 19 — about the same time as the 1991–2020 average (Feb 19).

average
Feb 192026
Feb 19

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 8b in Oregon

661 plants native to the lower 48 states, recorded in Oregon, and rated by the USDA to survive 15 °F or colder — the bottom of zone 8b. 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 Yamhill, OR.

Soil in Yamhill, OR

The soil mapped at the center of ZIP 97148 is Witham — silty clay loam, somewhat poorly drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up

pH5.5moderately acidic; most vegetables like 6.0–7.0

DrainageSomewhat poorly drainedconsider raised beds

Organic matter5.5%high

Hydrologic groupDwater soaks in very slowly

Farmland classFarmland of statewide importanceUSDA classification

Map unit: Witham silty clay loam, hummocky, 2 to 25 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 97148; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Yamhill, OR

Summer high83 °Faverage high, July

Winter low35 °Faverage low, December

Hot days19days a year at 90 °F or more

Freezing nights46nights a year at 32 °F or less

Growing degree days2,476base 50 °F — the season’s usable heat

Longest day15 h 40 mindaylight on June 21

Shortest day8 h 43 mindaylight on December 21

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

Precipitation45 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Mc Minnville, OR (11 mi away); precipitation: Yamhill 1.1 Nnw, OR (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8b.

Mcminnville, OR · 10 mi

971278b

Lafayette, OR · 11 mi

971158b

Dundee, OR · 13 mi

971138b

Cornelius, OR · 15 mi

971148b

Dayton, OR · 15 mi

971168b

Forest Grove, OR · 16 mi

Oregon planting zones →

Questions about 97148

What planting zone is ZIP code 97148?

ZIP code 97148 (Yamhill, OR) is in USDA hardiness zone 8b on the 2023 map: the coldest night of an average winter reaches 15 to 20 °F (−9.4 to −6.7 °C).

When is the last frost in Yamhill, OR?

The median last spring frost (32 °F) near 97148 is April 5; after April 27 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Mc Minnville station.

When is the first frost in Yamhill, OR?

The median first fall frost near 97148 is November 7, giving a median frost-free growing season of 216 days.

When should I plant tomatoes in 97148?

Start tomato seeds indoors around Feb 8 – Feb 22 and set transplants outside around Apr 12 – Apr 26, one to three weeks after the median last frost.

How much rain and snow does 97148 get?

About 45 inches of precipitation a year (NOAA 1991–2020 normals, Yamhill 1.1 Nnw station).

How hot do summers get in Yamhill, OR?

The average high peaks at 83 °F in July, with about 19 days a year at 90 °F or more.

What kind of soil does 97148 have?

The USDA soil survey maps Witham at the center of ZIP 97148: silty clay loam, somewhat poorly drained, pH about 5.5 (moderately acidic).

Did spring come early in Yamhill, OR in 2026?

Spring leaf-out near 97148 came on Feb 19 in 2026, about the same as the 1991–2020 average (Feb 19), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Yamhill, OR?

Long-day onions: the longest day near 97148 is 15 h 40 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).