Planting zone for 98546 — Grapeview, WA
ZIP code 98546 (Grapeview, Mason County) is in USDA zone 8b: the coldest winter night averages 15 to 20 °F. The median last spring frost is March 24 and the first fall frost November 15.
Where ZIP 98546 is
Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoomNot 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.
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 ServiceLoading the forecast for Grapeview, 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 Grapeview, WA
A hard freeze (28 °F) usually ends around February 20 and returns around December 7.
From the NOAA station Cushman Powerhouse #2, WA — 12 miles away, elevation 20 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 98546
Counted from the median last spring frost (Mar 24) and first fall frost (Nov 15) 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 98546 came on Feb 23 — about the same time as the 1991–2020 average (Feb 25).
Feb 252026
Feb 23
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 Grapeview, WA
The soil mapped at the center of ZIP 98546 is Alderwood — gravelly sandy loam, moderately well drained.
Map unit: Alderwood gravelly sandy loam, 8 to 15 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 98546; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.
Climate in Grapeview, WA
Average high and low, by month
Precipitation by month inches
NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Cushman Powerhouse #2, WA (12 mi away); precipitation: Shelton 5.9 Nne, WA (6 mi away). Daylight is calculated from latitude.
Nearby ZIP codes
All 8 nearest ZIP codes share zone 8b.
Questions about 98546
What planting zone is ZIP code 98546?
ZIP code 98546 (Grapeview, 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 Grapeview, WA?
The median last spring frost (32 °F) near 98546 is March 24; after April 17 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Cushman Powerhouse #2 station.
When is the first frost in Grapeview, WA?
The median first fall frost near 98546 is November 15, giving a median frost-free growing season of 235 days.
When should I plant tomatoes in 98546?
Start tomato seeds indoors around Jan 27 – Feb 10 and set transplants outside around Mar 31 – Apr 14, one to three weeks after the median last frost.
How much rain and snow does 98546 get?
About 67.9 inches of precipitation a year (NOAA 1991–2020 normals, Shelton 5.9 Nne station).
How hot do summers get in Grapeview, WA?
The average high peaks at 76 °F in July, with about 2 days a year at 90 °F or more.
What kind of soil does 98546 have?
The USDA soil survey maps Alderwood at the center of ZIP 98546: gravelly sandy loam, moderately well drained, pH about 5.8 (moderately acidic).
Did spring come early in Grapeview, WA in 2026?
Spring leaf-out near 98546 came on Feb 23 in 2026, about the same as the 1991–2020 average (Feb 25), according to the USA National Phenology Network Spring Index.
What kind of onions grow in Grapeview, WA?
Long-day onions: the longest day near 98546 is 15 h 57 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).