Kwethluk, Alaska, sits in USDA hardiness zone 4a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Growers here do well with cabbage, cranberry, cilantro, and collard greens — with the usual caveat that any single yard's soil, sun, and drainage cast the deciding vote.
Even in Kwethluk, 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 Kwethluk 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 Kwethluk — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Kwethluk — the short answer
Kwethluk, Alaska: USDA zone 4a, about 142 days between hard freezes, across 6K acres of city.
- USDA zone
- 4a
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 10
- Bethel Census Area normal — NOAA 1991–2020, nearest to this town
- First hard freeze (28°F)
- Sep 29
- Bethel Census Area normal — NOAA 1991–2020, nearest to this town
- Days between freezes
- ~142
- Bethel Census Area normal — NOAA 1991–2020, nearest to this town
- City area
- 6K 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 Bethel Census Area’s — the closest measured record, labelled as such rather than passed off as local.
Hardiness Zone Range
Zone 4a is Kwethluk's average, not your lot's — a low corner or a tree line moves it. Against Kwethluk's 142-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Kwethluk
Each reading below is measured for Kwethluk itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
From county recordsKwethluk runs about 142 days between hard freezes (read from Bethel Census Area, the closest normal to Kwethluk) — 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
MeasuredKwethluk sits in USDA hardiness zone 4a.
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
What Grows in Kwethluk
Every plant below cleared Kwethluk's own zone 4a and its 142-day season. Each card opens that plant's Alaska profile. How we score.
Is it too late to plant in Kwethluk?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Apr 12; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 10 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Sep 29 — long-season crops need about 90 days of runway, quick greens only 30. When the window is tight, the fall moves are quick ones — baby greens, radishes, and garlic set for next season.
What's on the federal record near Kwethluk
Closest first, within ~10 miles of Kwethluk. Listing isn't leaking, and distance isn't exposure.
- SB00806905CAAB1 001Nitrate · 1.3 mi
- SB01006936DCAA1 001Nitrate · 8.0 mi
- CROWLEY MARINE SERVICES - BETHELBrownfields · 8.4 mi
- CROWLEY MARINE SERVICES - BETHELToxics Release Inventory · 8.4 mi
- SB00807122ABAC1 002Nitrate · 9.7 mi
Measured from Kwethluk'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 Kwethluk.
Total Sites
8
within ~10 miles of Kwethluk
Risk Level
Low
Highest-severity
1 Toxics Release Inventory facility
Severity Distribution
within ~10 miles of Kwethluk
Highest-Severity Sites
Know Before You Grow
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
- •Near a brownfield, raised beds of imported soil give your food clean ground.
- •TRI facilities report what they release. Check the wind — downwind beds catch more of it.
Check your specific parcel in Kwethluk
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 Kwethluk average
Your land is one point inside Kwethluk
Everything above resolves to Kwethluk as a whole — one PHZM band, read across 6K acres, with hard-freeze dates borrowed from Bethel Census Area’s record because no 30-year normal resolves at this city’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 city 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 Kwethluk Average
Kwethluk Average
- ●USDA Zones 4a, averaged across Kwethluk
- ●One soil character for all of Kwethluk
- ●Frost dates read at Kwethluk's scale: May 10 to Sep 29
YOUR Parcel
- ✓Your exact zone, not Kwethluk's 4a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Kwethluk
Pull a site-specific report for your exact address in Kwethluk, Alaska — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Kwethluk averages can't show:
We read public map data around Kwethluk — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Kwethluk average
How we know this about Kwethluk
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Bethel Census Area’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 city grain anywhere on this page — there is no city-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 Kwethluk
When does frost risk typically end in Kwethluk?
The last hard freeze (28°F) in Kwethluk typically lands around May 10, 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 May 31.
When is the first frost in Kwethluk?
The first hard freeze (28°F) in Kwethluk typically arrives around Sep 29, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 15, so the watching starts about Aug 30 — about 142 days after the spring freeze cleared.
How long is the growing season in Kwethluk?
Measured between 28°F hard freezes, Kwethluk sees about 142 frost-free days — roughly May 10 through Sep 29, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 31 to Sep 15, about 107 days.
Is the soil safe to grow vegetables in Kwethluk?
The federal record around Kwethluk is light — 8 documented sites across the 9 federal source types we checked, mostly Nitrate entries (6), the nearest Nitrate record about 1.3 miles out — and proximity to a documented site is information, not a diagnosis of any one yard. Growing food here starts from a strong position; a soil test before new food beds settles any site-specific question.
How do gardeners stretch the season in Kwethluk?
With about 142 frost-free days between hard freezes, Kwethluk 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 170 to 198 days — and cold frames or low tunnels buy more. Starting transplants indoors ahead of the May 10 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Kwethluk's scale — its 4a band and its 142-day season. Your yard writes its own version of Kwethluk'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 Kwethluk’s own scale
4 of the readings below were taken at Kwethluk's own scale — the 6,492 acres it covers and 8 documented sites around it; 5 are borrowed from a wider read, named and linked below.
Measured here
- Kwethluk's own USDA hardiness band, zones 4aUSDA PHZM 2023
- 8 documented contamination sites on the federal record near Kwethluk, the closest Nitrate record about 1.3 miles out from the town centreFederal environmental registers
- Kwethluk's boundary and the 6,492 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4a and a ~142-day seasonGrowable Ground crop-matching engine
Inherited from a wider read
- The 28°F hard-freeze dates — Kwethluk has no normal of its own, so its county's is the closest measured readfrom Bethel Census Area
- Soil character — no town-scale survey exists, so Kwethluk's 6,492 acres read through its county's SSURGO summaryfrom Bethel County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Bethel County
- The growing challenges every Alaska grower plans around — written at state scale, so they stay on the state guidefrom Alaska
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Bethel County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Kwethluk's 6,492 acreswhy one lot differs from the next →
- Which side of Kwethluk you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 6,492 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 1.3 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 Kwethluk-wide figureread your own land →
More in Alaska
Wider growing context
What grows across AlaskaKwethluk sits outside our named growing regions, so Alaska as a whole is its closest context here.
Nearby growing guides