Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 98220 — Acme, WA

ZIP code 98220 (Acme, Whatcom County) is in USDA zone 8a: the coldest winter night averages 10 to 15 °F. The median last spring frost is March 27 and the first fall frost November 6.

Where ZIP 98220 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.

Zone8a10 to 15 °F

Coldest night−12.2 to −9.4 °C

Last frostMar 27

First frostNov 6

2012 zone8a

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 8a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Acme, 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 Acme, WA

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostMarch 27median — 50% chance of a later frost

Safe for tender plantsApril 17only 10% chance of frost after

First fall frostNovember 6median — 10% chance by Oct 15

Growing season224 daysfrost-free, median

A hard freeze (28 °F) usually ends around March 1 and returns around November 24.

From the NOAA station Sedro-Woolley, WA — 13 miles away, elevation 59 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 98220

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Feb 13 – Feb 27

SpinachSow outdoors · Feb 13 – Mar 6

Broccoli, cabbageStart indoors · Jan 16 – Jan 30

Broccoli, cabbageTransplant · Mar 6 – Mar 20

Onion setsPlant outdoors · Feb 27 – Mar 13

PotatoesPlant outdoors · Mar 6 – Mar 20

LettuceSow outdoors · Feb 27 – Mar 13

Carrots, beetsSow outdoors · Mar 6 – Mar 20

TomatoesStart indoors · Jan 30 – Feb 13

TomatoesTransplant · Apr 3 – Apr 17

Peppers, eggplantStart indoors · Jan 16 – Jan 30

Peppers, eggplantTransplant · Apr 10 – Apr 24

BeansSow outdoors · Apr 3 – Apr 17

Sweet cornSow outdoors · Apr 3 – Apr 17

Cucumbers, squashSow outdoors · Apr 3 – Apr 17

Fall lettuce, spinachSow outdoors · Sep 11 – Sep 25

GarlicPlant cloves · Oct 23 – Nov 27

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Mar 27) and first fall frost (Nov 6) 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 98220 came on Mar 5 — 4 days earlier than the 1991–2020 average (Mar 9).

average
Mar 92026
Mar 5

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 8a in Washington

611 plants native to the lower 48 states, recorded in Washington, and rated by the USDA to survive 10 °F or colder — the bottom of zone 8a. Each links to its USDA PLANTS profile.

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 Acme, WA.

Soil in Acme, WA

The soil mapped at the center of ZIP 98220 is Wickersham — channery ashy silt loam, well drained.

TextureChannery ashy silt loama good balance for most vegetables

pH5.8moderately acidic; most vegetables like 6.0–7.0

DrainageWell drainednatural drainage class

Organic matter6%high

Hydrologic groupBwater soaks in moderately

Farmland classprime farmlandUSDA classification

Map unit: Wickersham channery silt loam, 0 to 8 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 98220; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Acme, WA

Summer high75 °Faverage high, July

Winter low34 °Faverage low, December

Hot days1days a year at 90 °F or more

Freezing nights46nights a year at 32 °F or less

Growing degree days1,803base 50 °F — the season’s usable heat

Longest day16 h 09 mindaylight on June 21

Shortest day8 h 16 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation52 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Sedro-Woolley, WA (13 mi away); precipitation: Bellingham 3.0 Sse, WA (11 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

982298a

Bellingham, WA · 9 mi

982848b

Sedro Woolley, WA · 10 mi

Bellingham, WA · 13 mi

982278b

Bellingham, WA · 14 mi

982288b

Bellingham, WA · 14 mi

982448a

Deming, WA · 14 mi

Washington planting zones →

Questions about 98220

What planting zone is ZIP code 98220?

ZIP code 98220 (Acme, WA) is in USDA hardiness zone 8a on the 2023 map: the coldest night of an average winter reaches 10 to 15 °F (−12.2 to −9.4 °C).

When is the last frost in Acme, WA?

The median last spring frost (32 °F) near 98220 is March 27; after April 17 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Sedro-Woolley station.

When is the first frost in Acme, WA?

The median first fall frost near 98220 is November 6, giving a median frost-free growing season of 224 days.

When should I plant tomatoes in 98220?

Start tomato seeds indoors around Jan 30 – Feb 13 and set transplants outside around Apr 3 – Apr 17, one to three weeks after the median last frost.

How much rain and snow does 98220 get?

About 52 inches of precipitation a year (NOAA 1991–2020 normals, Bellingham 3.0 Sse station).

How hot do summers get in Acme, WA?

The average high peaks at 75 °F in July, with about 1 days a year at 90 °F or more.

What kind of soil does 98220 have?

The USDA soil survey maps Wickersham at the center of ZIP 98220: channery ashy silt loam, well drained, pH about 5.8 (moderately acidic).

Did spring come early in Acme, WA in 2026?

Spring leaf-out near 98220 came on Mar 5 in 2026, 4 days earlier than the 1991–2020 average (Mar 9), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Acme, WA?

Long-day onions: the longest day near 98220 is 16 h 09 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).