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

Planting zone for 97531 — Kerby, OR

ZIP code 97531 (Kerby, Josephine County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is May 1 and the first fall frost October 12.

Where ZIP 97531 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 frostMay 1
First frostOct 12
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 Kerby, 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 Kerby, OR

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 1median — 50% chance of a later frost
Safe for tender plantsMay 23only 10% chance of frost after
First fall frostOctober 12median — 10% chance by Sep 23
Growing season161 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 4 and returns around November 2.

From the NOAA station Cave Junction 1 Wnw, OR — 4 miles away, elevation 1,378 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 97531

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 20 – Apr 3
SpinachSow outdoors · Mar 20 – Apr 10
Broccoli, cabbageStart indoors · Feb 20 – Mar 6
Broccoli, cabbageTransplant · Apr 10 – Apr 24
Onion setsPlant outdoors · Apr 3 – Apr 17
PotatoesPlant outdoors · Apr 10 – Apr 24
LettuceSow outdoors · Apr 3 – Apr 17
Carrots, beetsSow outdoors · Apr 10 – Apr 24
TomatoesStart indoors · Mar 6 – Mar 20
TomatoesTransplant · May 8 – May 22
Peppers, eggplantStart indoors · Feb 20 – Mar 6
Peppers, eggplantTransplant · May 15 – May 29
BeansSow outdoors · May 8 – May 22
Sweet cornSow outdoors · May 8 – May 22
Cucumbers, squashSow outdoors · May 8 – May 22
Fall lettuce, spinachSow outdoors · Aug 17 – Aug 31
GarlicPlant cloves · Sep 28 – Nov 2
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 1) and first fall frost (Oct 12) 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 97531 came on Feb 24 — 5 days later than the 1991–2020 average (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).

Soil in Kerby, OR

The soil mapped at the center of ZIP 97531 is Josephine — moderately decomposed plant material, well drained.

TextureModerately decomposed plant materialtop layer
pH4.5strongly 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: Josephine gravelly loam, 20 to 35 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 97531; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Kerby, OR

Summer high94 °Faverage high, July
Winter low33 °Faverage low, January
Hot days73days a year at 90 °F or more
Freezing nights75nights a year at 32 °F or less
Growing degree days2,951base 50 °F — the season’s usable heat
Longest day15 h 16 mindaylight on June 21
Shortest day9 h 05 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation54.8 inper year, rain and melted snow

Average high and low, by month

20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 49 °F, low 33 °F 49°33° JanFebruary: average high 55 °F, low 33 °F 55°33° FebMarch: average high 60 °F, low 34 °F 60°34° MarApril: average high 67 °F, low 37 °F 67°37° AprMay: average high 76 °F, low 42 °F 76°42° MayJune: average high 84 °F, low 47 °F 84°47° JunJuly: average high 94 °F, low 52 °F 94°52° JulAugust: average high 94 °F, low 49 °F 94°49° AugSeptember: average high 87 °F, low 44 °F 87°44° SepOctober: average high 72 °F, low 39 °F 72°39° OctNovember: average high 55 °F, low 36 °F 55°36° NovDecember: average high 47 °F, low 33 °F 47°33° Dec

Precipitation by month inches

0″2″4″6″8″10″January: 10.21 in precipitation 10.2 JanFebruary: 6.31 in precipitation 6.3 FebMarch: 6.49 in precipitation 6.5 MarApril: 4.27 in precipitation 4.3 AprMay: 2.30 in precipitation 2.3 MayJune: 0.90 in precipitation 0.9 JunJuly: 0.31 in precipitation 0.3 JulAugust: 0.34 in precipitation 0.3 AugSeptember: 0.93 in precipitation 0.9 SepOctober: 3.38 in precipitation 3.4 OctNovember: 8.56 in precipitation 8.6 NovDecember: 10.75 in precipitation 10.8 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Cave Junction 1 Wnw, OR (4 mi away); precipitation: Cave Junction 0.4 Ene, OR (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

975388b
Selma, OR · 7 mi
975238b
Cave Junction, OR · 7 mi
975438b
Wilderville, OR · 12 mi
975348b
O Brien, OR · 13 mi
975448b
Williams, OR · 18 mi
975278b
Grants Pass, OR · 18 mi
975288b
Grants Pass, OR · 23 mi
955438a
Gasquet, CA · 24 mi

Oregon planting zones →

Questions about 97531

What planting zone is ZIP code 97531?

ZIP code 97531 (Kerby, 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 Kerby, OR?

The median last spring frost (32 °F) near 97531 is May 1; after May 23 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Cave Junction 1 Wnw station.

When is the first frost in Kerby, OR?

The median first fall frost near 97531 is October 12, giving a median frost-free growing season of 161 days.

When should I plant tomatoes in 97531?

Start tomato seeds indoors around Mar 6 – Mar 20 and set transplants outside around May 8 – May 22, one to three weeks after the median last frost.

How much rain and snow does 97531 get?

About 54.8 inches of precipitation a year (NOAA 1991–2020 normals, Cave Junction 0.4 Ene station).

How hot do summers get in Kerby, OR?

The average high peaks at 94 °F in July, with about 73 days a year at 90 °F or more.

What kind of soil does 97531 have?

The USDA soil survey maps Josephine at the center of ZIP 97531: moderately decomposed plant material, well drained, pH about 4.5 (strongly acidic).

Did spring come early in Kerby, OR in 2026?

Spring leaf-out near 97531 came on Feb 24 in 2026, 5 days later than the 1991–2020 average (Feb 19), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Kerby, OR?

Long-day onions: the longest day near 97531 is 15 h 16 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).