Custer, Washington, sits in USDA hardiness zone 8b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Well-matched crops include kale, potato, garlic, and western red cedar, and the gap between "grows in the area" and "grows in your yard" is closed by soil, sun, and drainage.
Even in Custer, no two yards are alike.
A low spot, a south-facing slope, or a stand of trees moves the frost date and sun across a single Custer lot. Enter your address and we'll score 1,086 plants against your land's actual soil, sun, and frost.
We read public map data around Custer — soil, climate, flood, and parcel records. How we handle your address.
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Custer — the short answer
Custer, Washington: USDA zone 8b, about 131 days between hard freezes, across 1K acres of town.
- USDA zone
- 8b
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 29
- Whatcom County normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Oct 7
- Whatcom County normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~131
- Whatcom County normal — NOAA 1991–2020, nearest to this town
- Town area
- 1K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. No 30-year normal resolves at this town’s own centroid, so the hard-freeze dates are Whatcom County’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 8b is Custer's average, not your lot's — a low corner or a tree line moves it. Against Custer's 131-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Custer
Each reading below is measured for Custer itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsCuster runs about 131 days between hard freezes (read from Whatcom County, the closest normal to Custer) — a short growing season.
Long-maturing crops like melons, sweet potatoes, and winter squash can run out of runway before the first hard freeze, ripening late or not at all.
Lead with fast-maturing varieties, and stretch the season on both ends with cold frames, low tunnels, or a greenhouse.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredCuster sits in USDA hardiness zone 8b.
The zone sets which perennials, shrubs, and fruit trees live through an average winter here — a plant rated for a colder zone is a safe bet, one rated warmer needs winter protection or gets treated as an annual.
Match perennials and fruit to the zone before you buy, so nothing you plant is a gamble against the cold.
USDA PHZM 2023
The kind of country Custer is in
Custer sits in the Puget Lowland — EPA Level III, inside the wider Marine West Coast Forest. That is read at Custer's own centroid, and it is not what its county reads: Whatcom County is mostly North Cascades. The wider page above you is answering a different question about different ground.
What Grows in Custer
Plants matched to Custer's USDA zones 8b, ordered by how much hardiness margin each has here — the ones with room to spare at both ends of this town's band lead. Each links to its full growing profile.
Is it too late to plant in Custer?
Almost never — the real question is what to plant next. Cool-season crops can go in from around May 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 29 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 7 — long-season crops need about 90 days of runway, quick greens only 30. In a season this compact, fast finishers and cold-hardy greens do the late work, and garlic tucked in before the freeze repays you next summer.
What's on the federal record near Custer
Closest first, within ~10 miles of Custer. Listing isn't leaking, and distance isn't exposure.
- WHATCOM COUNTY FIRE DISTRICT 13Underground Storage Tanks · 1900 ft
- CUSTER SCHOOLUnderground Storage Tanks · 2300 ft
- WA DOT CUSTER MAINTENANCE FACILITY SITEUnderground Storage Tanks · 2500 ft
- GRANDVIEW GOLF COURSEUnderground Storage Tanks · 0.6 mi
- 39N/01E-01C01Nitrate · 0.7 mi
- CUSTER SUBSTATIONUnderground Storage Tanks · 0.7 mi
- BONNEVILLE POWER ADMIN CUSTER SUBSTATIONBrownfields · 0.7 mi
- CUSTER GARAGEUnderground Storage Tanks · 1.2 mi
- ED PROMEROY DAIRYCAFO · 1.4 mi
- THE POMEROY FARM LLCCAFO · 1.5 mi
- MONTIGO DEL RAY CORPBrownfields · 1.6 mi
- HEALTHY PETToxics Release Inventory · 1.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Custer's center, not your beds. Run your own address for what's upwind of you specifically.
Environmental Intelligence
The counts behind that headline — every source type on the record near Custer.
Total Sites
632
within ~10 miles of Custer
Risk Level
Elevated
Highest-severity
5 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Custer
Severity Distribution
within ~10 miles of Custer
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Custer, two things run higher than the national average within ~10 miles of Custer — CAFO (65 sites) and Nitrate (290 sites). That's not a problem with your land — it's information about it.
CAFO: CAFOs pose a different contamination profile than chemical sources.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Wash all produce consumed raw thoroughly, especially leafy greens grown near CAFOs.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Custer
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,086 plant recommendations.
25+ data sources read at your address, not the Custer average
Your land is one point inside Custer
Everything above resolves to Custer as a whole — one PHZM band, read across 1K acres, with hard-freeze dates borrowed from Whatcom County’s record because no 30-year normal resolves at this town’s own centroid. Your parcel is one point inside that footprint. Slope, tree cover, a low spot that pools cold air, and what is in the soil are all resolved at the address, and none of them are visible at town scale. That is the honest boundary of this page, and the reason the next step is a reading of your own ground rather than a better local average.
Your Lot vs the Custer Average
Custer Average
- ●USDA Zones 8b, averaged across Custer
- ●One soil character for all of Custer
- ●Frost dates read at Custer's scale: May 29 to Oct 7
YOUR Parcel
- ✓Your exact zone, not Custer's 8b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Custer
Pull a site-specific report for your exact address in Custer, Washington — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Custer averages can't show:
We read public map data around Custer — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Custer average
How we know this about Custer
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this town’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Whatcom County’s record, because none resolves here; boundaries and acreage from US Census TIGER/Line 2025; the contamination records from the federal sources named in their beats above. Soil is not read at town grain anywhere on this page — there is no town-resolution survey in our data, which is why you will find no soil grid here rather than a statewide one wearing a local label. The resolution ledger below names every figure this page inherited.
Common questions about Custer
When does frost risk typically end in Custer?
The last hard freeze (28°F) in Custer typically lands around May 29, per NOAA 1991–2020 climate normals — earlier than the light-frost dates most charts quote. That marks the hard freeze, not the last light frost — lighter frosts keep biting past it, which is why tender transplants here wait until about Jun 19.
When is the first frost in Custer?
The first hard freeze (28°F) in Custer typically arrives around Oct 7, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 23, so the watching starts about Sep 7 — about 131 days after the spring freeze cleared.
How long is the growing season in Custer?
Measured between 28°F hard freezes, Custer sees about 131 frost-free days — roughly May 29 through Oct 7, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Jun 19 to Sep 23, about 96 days.
Is the soil safe to grow vegetables in Custer?
The federal record around Custer is a meaningful one — 632 documented sites, mostly Nitrate entries (290), the nearest Underground Storage Tanks record about 0.4 miles out — so a soil test before new food beds is a sensible precaution here, not a reason to hold back from growing. Remember that proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what sits where.
How do gardeners stretch the season in Custer?
With about 131 frost-free days between hard freezes, Custer rewards the classic extension moves: floating row cover buys roughly two to four extra weeks at each shoulder — on this season that is a working window nearer 159 to 187 days — and cold frames or low tunnels buy more. Starting transplants indoors ahead of the May 29 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Custer's scale — its 8b band and its 131-day season. Your yard writes its own version of Custer's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
What this page reads at Custer’s own scale
4 of the readings below were taken at Custer's own scale — the 1,436 acres it covers and 632 documented sites around it; 6 are borrowed from a wider read, named and linked below.
Measured here
- Custer's own USDA hardiness band, zones 8bUSDA PHZM 2023
- 632 documented contamination sites on the federal record near Custer, the closest Underground Storage Tanks record about 0.4 miles out from the town centreFederal environmental registers
- Custer's boundary and the 1,436 acres inside itUS Census TIGER/Line 2025
- Custer sits in the Puget Lowland — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- The 28°F hard-freeze dates — Custer has no normal of its own, so its county's is the closest measured readfrom Whatcom County
- Soil character — no town-scale survey exists, so Custer's 1,436 acres read through its county's SSURGO summaryfrom Whatcom County
- The candidate plant list — Washington's curated set, filtered to this zone band and re-ordered by how much margin each has herefrom Washington
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Whatcom County
- The growing challenges every Washington grower plans around — written at state scale, so they stay on the state guidefrom Washington
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Whatcom County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Custer's 1,436 acreswhy one lot differs from the next →
- Which side of Custer you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,436 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.4 miles out, measured from the town centrehow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — measured at your address, and averaged away by any Custer-wide figureread your own land →
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