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

Planting zone for 97378 — Sheridan, OR

ZIP code 97378 (Sheridan, Yamhill County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is April 16 and the first fall frost November 1.

Where ZIP 97378 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 16
First frostNov 1
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 Sheridan, 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 Sheridan, OR

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 16median — 50% chance of a later frost
Safe for tender plantsMay 5only 10% chance of frost after
First fall frostNovember 1median — 10% chance by Oct 13
Growing season199 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 7 and returns around November 20.

From the NOAA station Dallas 2 Ne, OR — 12 miles away, elevation 289 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 97378

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 5 – Mar 19
SpinachSow outdoors · Mar 5 – Mar 26
Broccoli, cabbageStart indoors · Feb 5 – Feb 19
Broccoli, cabbageTransplant · Mar 26 – Apr 9
Onion setsPlant outdoors · Mar 19 – Apr 2
PotatoesPlant outdoors · Mar 26 – Apr 9
LettuceSow outdoors · Mar 19 – Apr 2
Carrots, beetsSow outdoors · Mar 26 – Apr 9
TomatoesStart indoors · Feb 19 – Mar 5
TomatoesTransplant · Apr 23 – May 7
Peppers, eggplantStart indoors · Feb 5 – Feb 19
Peppers, eggplantTransplant · Apr 30 – May 14
BeansSow outdoors · Apr 23 – May 7
Sweet cornSow outdoors · Apr 23 – May 7
Cucumbers, squashSow outdoors · Apr 23 – May 7
Fall lettuce, spinachSow outdoors · Sep 6 – Sep 20
GarlicPlant cloves · Oct 18 – Nov 22
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 16) and first fall frost (Nov 1) 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 97378 came on Feb 23 — 5 days later than the 1991–2020 average (Feb 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 Sheridan, OR

The soil mapped at the center of ZIP 97378 is Woodburn — silt loam, moderately well drained.

TextureSilt loama good balance for most vegetables
pH5.9moderately acidic; most vegetables like 6.0–7.0
DrainageModerately well drainednatural drainage class
Organic matter3.9%moderate
Hydrologic groupCwater soaks in slowly
Farmland classprime farmlandUSDA classification

Map unit: Woodburn silt loam, 0 to 3 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 97378; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Sheridan, OR

Summer high83 °Faverage high, July
Winter low35 °Faverage low, January
Hot days17days a year at 90 °F or more
Freezing nights49nights a year at 32 °F or less
Growing degree days2,317base 50 °F — the season’s usable heat
Longest day15 h 38 mindaylight on June 21
Shortest day8 h 45 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation46.9 inper year, rain and melted snow

Average high and low, by month

20°30°40°50°60°70°80°90°32 °FJanuary: average high 47 °F, low 35 °F 47°35° JanFebruary: average high 51 °F, low 36 °F 51°36° FebMarch: average high 56 °F, low 38 °F 56°38° MarApril: average high 61 °F, low 40 °F 61°40° AprMay: average high 68 °F, low 45 °F 68°45° MayJune: average high 73 °F, low 49 °F 73°49° JunJuly: average high 83 °F, low 52 °F 83°52° JulAugust: average high 83 °F, low 52 °F 83°52° AugSeptember: average high 78 °F, low 49 °F 78°49° SepOctober: average high 65 °F, low 44 °F 65°44° OctNovember: average high 52 °F, low 38 °F 52°38° NovDecember: average high 46 °F, low 35 °F 46°35° Dec

Precipitation by month inches

0″2″4″6″8″January: 7.14 in precipitation 7.1 JanFebruary: 4.79 in precipitation 4.8 FebMarch: 4.64 in precipitation 4.6 MarApril: 3.58 in precipitation 3.6 AprMay: 2.53 in precipitation 2.5 MayJune: 1.47 in precipitation 1.5 JunJuly: 0.34 in precipitation 0.3 JulAugust: 0.46 in precipitation 0.5 AugSeptember: 1.62 in precipitation 1.6 SepOctober: 4.07 in precipitation 4.1 OctNovember: 7.78 in precipitation 7.8 NovDecember: 8.49 in precipitation 8.5 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Dallas 2 Ne, OR (12 mi away); precipitation: Sheridan 2.1 Nnw, OR (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 8b.

973968b
Willamina, OR · 6 mi
971018b
Amity, OR · 9 mi
973388b
Dallas, OR · 11 mi
971288b
Mcminnville, OR · 11 mi
973478b
Grand Ronde, OR · 12 mi
973718b
Rickreall, OR · 13 mi
973448b
Falls City, OR · 15 mi
973048b
Salem, OR · 16 mi

Oregon planting zones →

Questions about 97378

What planting zone is ZIP code 97378?

ZIP code 97378 (Sheridan, 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 Sheridan, OR?

The median last spring frost (32 °F) near 97378 is April 16; after May 5 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Dallas 2 Ne station.

When is the first frost in Sheridan, OR?

The median first fall frost near 97378 is November 1, giving a median frost-free growing season of 199 days.

When should I plant tomatoes in 97378?

Start tomato seeds indoors around Feb 19 – Mar 5 and set transplants outside around Apr 23 – May 7, one to three weeks after the median last frost.

How much rain and snow does 97378 get?

About 46.9 inches of precipitation a year (NOAA 1991–2020 normals, Sheridan 2.1 Nnw station).

How hot do summers get in Sheridan, OR?

The average high peaks at 83 °F in July, with about 17 days a year at 90 °F or more.

What kind of soil does 97378 have?

The USDA soil survey maps Woodburn at the center of ZIP 97378: silt loam, moderately well drained, pH about 5.9 (moderately acidic).

Did spring come early in Sheridan, OR in 2026?

Spring leaf-out near 97378 came on Feb 23 in 2026, 5 days later than the 1991–2020 average (Feb 18), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Sheridan, OR?

Long-day onions: the longest day near 97378 is 15 h 38 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).