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

Planting zone for 98589 — Tenino, WA

ZIP code 98589 (Tenino, Thurston County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is April 22 and the first fall frost October 27.

Where ZIP 98589 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 22
First frostOct 27
2012 zone8a

Was 8a 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 8b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Tenino, WA…

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 Tenino, WA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 22median — 50% chance of a later frost
Safe for tender plantsMay 10only 10% chance of frost after
First fall frostOctober 27median — 10% chance by Oct 7
Growing season188 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 23 and returns around November 13.

From the NOAA station Centralia, WA — 11 miles away, elevation 184 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 98589

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 11 – Mar 25
SpinachSow outdoors · Mar 11 – Apr 1
Broccoli, cabbageStart indoors · Feb 11 – Feb 25
Broccoli, cabbageTransplant · Apr 1 – Apr 15
Onion setsPlant outdoors · Mar 25 – Apr 8
PotatoesPlant outdoors · Apr 1 – Apr 15
LettuceSow outdoors · Mar 25 – Apr 8
Carrots, beetsSow outdoors · Apr 1 – Apr 15
TomatoesStart indoors · Feb 25 – Mar 11
TomatoesTransplant · Apr 29 – May 13
Peppers, eggplantStart indoors · Feb 11 – Feb 25
Peppers, eggplantTransplant · May 6 – May 20
BeansSow outdoors · Apr 29 – May 13
Sweet cornSow outdoors · Apr 29 – May 13
Cucumbers, squashSow outdoors · Apr 29 – May 13
Fall lettuce, spinachSow outdoors · Sep 1 – Sep 15
GarlicPlant cloves · Oct 13 – Nov 17
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 22) and first fall frost (Oct 27) 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 98589 came on Feb 22 — 5 days earlier than the 1991–2020 average (Feb 27).

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 Tenino, WA

The soil mapped at the center of ZIP 98589 is Melbourne — silty clay loam, well drained.

TextureSilty clay loamholds water and nutrients; slow to drain and warm up
pH6.1slightly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter5.5%high
Hydrologic groupCwater soaks in slowly
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Melbourne silty clay loam, 5 to 20 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 98589; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Tenino, WA

Summer high78 °Faverage high, July
Winter low34 °Faverage low, January
Hot days8days a year at 90 °F or more
Freezing nights48nights a year at 32 °F or less
Growing degree days1,943base 50 °F — the season’s usable heat
Longest day15 h 52 mindaylight on June 21
Shortest day8 h 32 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation41.6 inper year, rain and melted snow

Average high and low, by month

20°30°40°50°60°70°80°90°32 °FJanuary: average high 46 °F, low 34 °F 46°34° JanFebruary: average high 50 °F, low 34 °F 50°34° FebMarch: average high 54 °F, low 36 °F 54°36° MarApril: average high 60 °F, low 39 °F 60°39° AprMay: average high 67 °F, low 44 °F 67°44° MayJune: average high 71 °F, low 49 °F 71°49° JunJuly: average high 78 °F, low 53 °F 78°53° JulAugust: average high 78 °F, low 53 °F 78°53° AugSeptember: average high 73 °F, low 48 °F 73°48° SepOctober: average high 61 °F, low 43 °F 61°43° OctNovember: average high 51 °F, low 37 °F 51°37° NovDecember: average high 45 °F, low 34 °F 45°34° Dec

Precipitation by month inches

0″2″4″6″January: 5.85 in precipitation 5.8 JanFebruary: 4.24 in precipitation 4.2 FebMarch: 4.39 in precipitation 4.4 MarApril: 3.24 in precipitation 3.2 AprMay: 2.44 in precipitation 2.4 MayJune: 1.53 in precipitation 1.5 JunJuly: 0.50 in precipitation 0.5 JulAugust: 0.84 in precipitation 0.8 AugSeptember: 1.59 in precipitation 1.6 SepOctober: 4.00 in precipitation 4.0 OctNovember: 6.53 in precipitation 6.5 NovDecember: 6.44 in precipitation 6.4 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Centralia, WA (11 mi away); precipitation: Centralia, WA (11 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

985308b
Bucoda, WA · 4 mi
985768b
Rainier, WA · 7 mi
985318b
Centralia, WA · 8 mi
985018a
Olympia, WA · 11 mi
985098b
Lacey, WA · 11 mi
985408a
East Olympia, WA · 11 mi
985138b
Olympia, WA · 11 mi
985448b
Galvin, WA · 13 mi

Washington planting zones →

Questions about 98589

What planting zone is ZIP code 98589?

ZIP code 98589 (Tenino, WA) 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 Tenino, WA?

The median last spring frost (32 °F) near 98589 is April 22; after May 10 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Centralia station.

When is the first frost in Tenino, WA?

The median first fall frost near 98589 is October 27, giving a median frost-free growing season of 188 days.

When should I plant tomatoes in 98589?

Start tomato seeds indoors around Feb 25 – Mar 11 and set transplants outside around Apr 29 – May 13, one to three weeks after the median last frost.

How much rain and snow does 98589 get?

About 41.6 inches of precipitation a year (NOAA 1991–2020 normals, Centralia station).

How hot do summers get in Tenino, WA?

The average high peaks at 78 °F in July, with about 8 days a year at 90 °F or more.

What kind of soil does 98589 have?

The USDA soil survey maps Melbourne at the center of ZIP 98589: silty clay loam, well drained, pH about 6.1 (slightly acidic).

Did spring come early in Tenino, WA in 2026?

Spring leaf-out near 98589 came on Feb 22 in 2026, 5 days earlier than the 1991–2020 average (Feb 27), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Tenino, WA?

Long-day onions: the longest day near 98589 is 15 h 52 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 98589 change?

Yes. The 2012 USDA map put 98589 in zone 8a; the 2023 map puts it in zone 8b. The newer map uses 1991–2020 data and more weather stations.