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

Planting zone for 98057 — Renton, WA

ZIP code 98057 (Renton, King County) is in USDA zone 9a: the coldest winter night averages 20 to 25 °F. The median last spring frost is March 13 and the first fall frost November 16.

Where ZIP 98057 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.

Zone9a20 to 25 °F
Coldest night−6.7 to −3.9 °C
Last frostMar 13
First frostNov 16
2012 zone8b

Was 8b 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 9a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Renton, 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 Renton, WA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMarch 13median — 50% chance of a later frost
Safe for tender plantsMarch 31only 10% chance of frost after
First fall frostNovember 16median — 10% chance by Oct 29
Growing season248 daysfrost-free, median

A hard freeze (28 °F) usually ends around February 13 and returns around December 6.

From the NOAA station Renton Municipal Airport, WA — within 1 mile, elevation 30 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 98057

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Jan 30 – Feb 13
SpinachSow outdoors · Jan 30 – Feb 20
Broccoli, cabbageStart indoors · Jan 2 – Jan 16
Broccoli, cabbageTransplant · Feb 20 – Mar 6
Onion setsPlant outdoors · Feb 13 – Feb 27
PotatoesPlant outdoors · Feb 20 – Mar 6
LettuceSow outdoors · Feb 13 – Feb 27
Carrots, beetsSow outdoors · Feb 20 – Mar 6
TomatoesStart indoors · Jan 16 – Jan 30
TomatoesTransplant · Mar 20 – Apr 3
Peppers, eggplantStart indoors · Jan 2 – Jan 16
Peppers, eggplantTransplant · Mar 27 – Apr 10
BeansSow outdoors · Mar 20 – Apr 3
Sweet cornSow outdoors · Mar 20 – Apr 3
Cucumbers, squashSow outdoors · Mar 20 – Apr 3
Fall lettuce, spinachSow outdoors · Sep 21 – Oct 5
GarlicPlant cloves · Nov 2 – Dec 7
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 13) and first fall frost (Nov 16) 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 98057 came on Feb 12 — 4 days earlier than the 1991–2020 average (Feb 16).

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 9a in Washington

617 plants native to the lower 48 states, recorded in Washington, and rated by the USDA to survive 20 °F or colder — the bottom of zone 9a. Each links to its USDA PLANTS profile.

Trees 32

Alaska cedar75 ft · blooms mid spring · low shade tolerance · to −22 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Fbalsam poplar80 ft · blooms late spring · high shade tolerance · to −79 °Fbigleaf maple60 ft · blooms mid spring · medium shade tolerance · to −14 °Fblack locust60 ft · blooms spring · high shade tolerance · to −37 °Fboxelder60 ft · blooms early spring · low shade tolerance · to −46 °F

Shrubs 115

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falpine laurel1 ft · blooms late spring · low shade tolerance · to −28 °FAmerican plum24 ft · blooms mid spring · high shade tolerance · to −38 °Fantelope bitterbrush6 ft · blooms early spring · medium shade tolerance · to −36 °FBarclay's willow15 ft · high shade tolerance · to −43 °F

Wildflowers & perennials 293

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °Falpine bistort1 ft · blooms mid spring · high shade tolerance · to −38 °Falpine mountainsorrel1 ft · blooms mid summer · medium shade tolerance · to −43 °FAmerican alpine speedwell1 ft · blooms summer · medium shade tolerance · to −28 °FAmerican bistort1.5 ft · blooms mid spring · high shade tolerance · to −38 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °F

Grasses 159

Alaska brome5 ft · blooms late spring · low shade tolerance · to −18 °FAlaska oniongrass3 ft · blooms mid spring · low shade tolerance · to −33 °Falkali cordgrass3 ft · blooms late summer · high shade tolerance · to −38 °Falkali sacaton3 ft · blooms mid summer · high shade tolerance · to −38 °Falpine timothy1.4 ft · blooms late spring · medium shade tolerance · to −43 °FAmerican beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °F

Vines 3

riverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Ftrumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °Fwestern white clematis1 ft · blooms mid summer · medium shade tolerance · to −38 °F

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 Renton, WA.

Soil in Renton, WA

The center of ZIP 98057 is mapped as Urban land: built-over ground without natural soil data. Garden soil here is usually imported or disturbed — test before you plant.

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 98057; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Renton, WA

Summer high78 °Faverage high, August
Winter low37 °Faverage low, January
Hot days4days a year at 90 °F or more
Freezing nights30nights a year at 32 °F or less
Growing degree days2,336base 50 °F — the season’s usable heat
Longest day15 h 58 mindaylight on June 21
Shortest day8 h 26 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation44 inper year, rain and melted snow

Average high and low, by month

30°40°50°60°70°80°90°32 °FJanuary: average high 48 °F, low 37 °F 48°37° JanFebruary: average high 50 °F, low 37 °F 50°37° FebMarch: average high 55 °F, low 40 °F 55°40° MarApril: average high 60 °F, low 43 °F 60°43° AprMay: average high 66 °F, low 49 °F 66°49° MayJune: average high 71 °F, low 54 °F 71°54° JunJuly: average high 77 °F, low 58 °F 77°58° JulAugust: average high 78 °F, low 57 °F 78°57° AugSeptember: average high 72 °F, low 53 °F 72°53° SepOctober: average high 61 °F, low 46 °F 61°46° OctNovember: average high 52 °F, low 40 °F 52°40° NovDecember: average high 47 °F, low 37 °F 47°37° Dec

Precipitation by month inches

0″2″4″6″8″January: 6.35 in precipitation 6.3 JanFebruary: 4.11 in precipitation 4.1 FebMarch: 4.37 in precipitation 4.4 MarApril: 3.65 in precipitation 3.6 AprMay: 2.26 in precipitation 2.3 MayJune: 1.63 in precipitation 1.6 JunJuly: 0.73 in precipitation 0.7 JulAugust: 1.00 in precipitation 1.0 AugSeptember: 1.84 in precipitation 1.8 SepOctober: 4.45 in precipitation 4.5 OctNovember: 7.04 in precipitation 7.0 NovDecember: 6.57 in precipitation 6.6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Renton Municipal Airport, WA (within 1 mile); precipitation: Renton 0.5 Ssw, WA (within 1 mile). 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.

980559a
Renton, WA · 2 mi
981789a
Seattle, WA · 2 mi
981889a
Seattle, WA · 3 mi
980569a
Renton, WA · 3 mi
981689a
Seattle, WA · 4 mi
981589a
Seattle, WA · 4 mi
980598b
Renton, WA · 4 mi
980318b
Kent, WA · 5 mi

All 5 ZIP codes in Renton → · Washington planting zones →

Questions about 98057

What planting zone is ZIP code 98057?

ZIP code 98057 (Renton, WA) is in USDA hardiness zone 9a on the 2023 map: the coldest night of an average winter reaches 20 to 25 °F (−6.7 to −3.9 °C).

When is the last frost in Renton, WA?

The median last spring frost (32 °F) near 98057 is March 13; after March 31 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Renton Municipal Airport station.

When is the first frost in Renton, WA?

The median first fall frost near 98057 is November 16, giving a median frost-free growing season of 248 days.

When should I plant tomatoes in 98057?

Start tomato seeds indoors around Jan 16 – Jan 30 and set transplants outside around Mar 20 – Apr 3, one to three weeks after the median last frost.

How much rain and snow does 98057 get?

About 44 inches of precipitation a year (NOAA 1991–2020 normals, Renton 0.5 Ssw station).

How hot do summers get in Renton, WA?

The average high peaks at 78 °F in August, with about 4 days a year at 90 °F or more.

Did spring come early in Renton, WA in 2026?

Spring leaf-out near 98057 came on Feb 12 in 2026, 4 days earlier than the 1991–2020 average (Feb 16), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Renton, WA?

Long-day onions: the longest day near 98057 is 15 h 58 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 98057 change?

Yes. The 2012 USDA map put 98057 in zone 8b; the 2023 map puts it in zone 9a. The newer map uses 1991–2020 data and more weather stations.