American Falls, Idaho, sits in USDA hardiness zone 6a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
Expect cabbage, blackberry, california poppy, and collard greens to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Even in American Falls, 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 American Falls 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 American Falls — soil, climate, flood, and parcel records. How we handle your address.
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American Falls — the short answer
American Falls, Idaho: USDA zone 6a, about 163 days between hard freezes, across 1K acres of city.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 1
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 11
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~163
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 1K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are this town’s own 28°F normals: light frosts run a few weeks past them, and tender transplants usually wait 2–3 weeks after the last hard freeze.
Hardiness Zone Range
Zone 6a is American Falls's average, not your lot's — a low corner or a tree line moves it. Against American Falls's 163-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in American Falls
Each reading below is measured for American Falls itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredAmerican Falls runs about 163 days between hard freezes — a moderate growing season.
There is room for the full run of cool-season crops plus a warm-season main crop, but the calendar is tight enough that a late spring or early fall frost still decides how much finishes.
Time warm-season transplants to your last hard freeze, and a few weeks of season extension turns a near-miss harvest into a sure one.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredAmerican Falls sits in USDA hardiness zone 6a.
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 American Falls is in
American Falls sits in the Snake River Plain — EPA Level III, inside the wider North American Deserts. That is read at American Falls's own centroid, and it is not what its county reads: Power County is mostly Northern Basin and Range. The wider page above you is answering a different question about different ground.
What Grows in American Falls
Every plant below cleared American Falls's own zone 6a and its 163-day season. Each card opens that plant's Idaho profile. How we score.
Is it too late to plant in American Falls?
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 3; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 1 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 11 — long-season crops need about 90 days of runway, quick greens only 30. As the window narrows, the plantings just get faster — fall brassicas, then greens, then garlic to finish.
What's on the federal record near American Falls
Closest first, within ~10 miles of American Falls. Listing isn't leaking, and distance isn't exposure.
- NICHOLS 66/ABC AUTOUnderground Storage Tanks · 500 ft
- ANDERSON'S BODY & GLASSBrownfields · 700 ft
- C & J CHAIN SAWSUnderground Storage Tanks · 800 ft
- MR PETROL'S PANTRY #2/SINCLAIRUnderground Storage Tanks · 900 ft
- AMERICAN FALLS SCHOOL DISUnderground Storage Tanks · 900 ft
- BINGHAM COOPERATIVE INCUnderground Storage Tanks · 1000 ft
- W & W QUICK PICKUnderground Storage Tanks · 1100 ft
- POWER COUNTY COURT HOUSEUnderground Storage Tanks · 1100 ft
- AMERICAN FALLS SD 381 INTERMEDIATE SCHOOLBrownfields · 1200 ft
- AMERICAN FALLSUnderground Storage Tanks · 1300 ft
- MICHAUDUnderground Storage Tanks · 1300 ft
- HILLTOP TRUCK STOPUnderground Storage Tanks · 1300 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from American Falls'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 American Falls.
Total Sites
152
within ~10 miles of American Falls
Risk Level
Elevated
Highest-severity
1 Toxics Release Inventory facility
Sources Checked
within ~10 miles of American Falls
Severity Distribution
within ~10 miles of American Falls
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around American Falls, Nitrate runs higher than the national average — 70 sites within ~10 miles of American Falls. Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in American Falls
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 American Falls average
Your land is one point inside American Falls
Everything above resolves to American Falls as a whole — one PHZM band and one 28°F frost record, read across 1K acres. 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 American Falls Average
American Falls Average
- ●USDA Zones 6a, averaged across American Falls
- ●One soil character for all of American Falls
- ●Frost dates read at American Falls's scale: May 1 to Oct 11
YOUR Parcel
- ✓Your exact zone, not American Falls's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in American Falls
Pull a site-specific report for your exact address in American Falls, Idaho — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that American Falls averages can't show:
We read public map data around American Falls — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the American Falls average
How we know this about American Falls
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 American Falls’s own record; 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 American Falls
When does frost risk typically end in American Falls?
The last hard freeze (28°F) in American Falls typically lands around May 1, 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 22.
When is the first frost in American Falls?
The first hard freeze (28°F) in American Falls typically arrives around Oct 11, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 27, so the watching starts about Sep 11 — about 163 days after the spring freeze cleared.
How long is the growing season in American Falls?
Measured between 28°F hard freezes, American Falls sees about 163 frost-free days — roughly May 1 through Oct 11, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 22 to Sep 27, about 128 days.
Is the soil safe to grow vegetables in American Falls?
The federal record around American Falls is a meaningful one — 152 documented sites, mostly Nitrate entries (70), the nearest Underground Storage Tanks record under a tenth of a mile 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 I protect my plants from frost in American Falls?
From about Sep 11 the job here turns from planting to protecting — the last start even a 30-day crop can finish. As the season closes around the first 28°F hard freeze near Oct 11 (NOAA 1991–2020 climate normals), three moves buy time: row cover or an old sheet over tender plants on still, clear nights; water the soil the afternoon before a freeze, so it holds warmth overnight; and harvest tomatoes, peppers and basil before Oct 11. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at American Falls's scale — its 6a band and its 163-day season. Your yard writes its own version of American Falls'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 American Falls’s own scale
6 of the readings below were taken at American Falls's own scale — its own ~163-day season between 28°F freezes, the 1,033 acres it covers and 152 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- American Falls's own USDA hardiness band, zones 6aUSDA PHZM 2023
- American Falls's own 28°F hard-freeze dates, about May 1 and Oct 11 and the ~163-day span between themNOAA 1991–2020 Climate Normals
- 152 documented contamination sites on the federal record near American Falls, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- American Falls's boundary and the 1,033 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~163-day seasonGrowable Ground crop-matching engine
- American Falls sits in the Snake River Plain — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so American Falls's 1,033 acres read through its county's SSURGO summaryfrom Power County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Power County
- The growing challenges every Idaho grower plans around — written at state scale, so they stay on the state guidefrom Idaho
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Power County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among American Falls's 1,033 acreswhy one lot differs from the next →
- Which side of American Falls you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,033 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record under a tenth of a mile 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 American Falls-wide figureread your own land →
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