Heyburn, Idaho, sits in USDA hardiness zone 6b — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
On paper, cabbage, blackberry, california poppy, and collard greens all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in Heyburn, 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 Heyburn 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 Heyburn — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Heyburn — the short answer
Heyburn, Idaho: USDA zone 6b, about 176 days between hard freezes, across 2K acres of city.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 23
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 16
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~176
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 2K 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 6b is Heyburn's average, not your lot's — a low corner or a tree line moves it. Against Heyburn's 176-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Heyburn
Each reading below is measured for Heyburn itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredHeyburn runs about 176 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
MeasuredHeyburn sits in USDA hardiness zone 6b.
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 Heyburn is in
Heyburn sits in the Snake River Plain — EPA Level III, inside the wider North American Deserts. That is read at Heyburn's own centroid rather than borrowed from Minidoka County.
What Grows in Heyburn
Every plant below cleared Heyburn's own zone 6b and its 176-day season. Each card opens that plant's Idaho profile. How we score.
Is it too late to plant in Heyburn?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 26; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 23 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 16 — long-season crops need about 90 days of runway, quick greens only 30. Late in the year the fall bench takes over — quick greens, radishes, and garlic that repays you next summer.
What's on the federal record near Heyburn
Closest first, within ~10 miles of Heyburn. Listing isn't leaking, and distance isn't exposure.
- MINIDOKA COUNTY'S DIST #331Underground Storage Tanks · 600 ft
- RALPH A COMBSUnderground Storage Tanks · 1500 ft
- Heyburn City ShopUnderground Storage Tanks · 1500 ft
- LARRY'S FOOD CENTERUnderground Storage Tanks · 1900 ft
- JR SIMPLOT CO HEYBURNUnderground Storage Tanks · 2200 ft
- J R SIMPLOT COMPANY HEYBURN FOOD GROUPToxics Release Inventory · 2200 ft
- Southwind FarmsUnderground Storage Tanks · 0.6 mi
- GOSSNER FOODSToxics Release Inventory · 0.8 mi
- SIMPLOT HEYBURN ETHANOL PLANTUnderground Storage Tanks · 0.8 mi
- 10S 23E 15CDC1Nitrate · 0.8 mi
- SCHOWS TRUCK CENTERBrownfields · 1.0 mi
- 10S 23E 11CCD2Nitrate · 1.1 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Heyburn'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 Heyburn.
Total Sites
488
within ~10 miles of Heyburn
Risk Level
Elevated
Highest-severity
4 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Heyburn
Severity Distribution
within ~10 miles of Heyburn
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Heyburn, two things run higher than the national average within ~10 miles of Heyburn — CAFO (8 sites) and Nitrate (210 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around 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 Heyburn
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 Heyburn average
Your land is one point inside Heyburn
Everything above resolves to Heyburn as a whole — one PHZM band and one 28°F frost record, read across 2K 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 Heyburn Average
Heyburn Average
- ●USDA Zones 6b, averaged across Heyburn
- ●One soil character for all of Heyburn
- ●Frost dates read at Heyburn's scale: Apr 23 to Oct 16
YOUR Parcel
- ✓Your exact zone, not Heyburn's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Heyburn
Pull a site-specific report for your exact address in Heyburn, Idaho — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Heyburn averages can't show:
We read public map data around Heyburn — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Heyburn average
How we know this about Heyburn
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 Heyburn’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 Heyburn
When does frost risk typically end in Heyburn?
The last hard freeze (28°F) in Heyburn typically lands around Apr 23, 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 14.
When is the first frost in Heyburn?
The first hard freeze (28°F) in Heyburn typically arrives around Oct 16, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 2, so the watching starts about Sep 16 — about 176 days after the spring freeze cleared.
How long is the growing season in Heyburn?
Measured between 28°F hard freezes, Heyburn sees about 176 frost-free days — roughly Apr 23 through Oct 16, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 14 to Oct 2, about 141 days.
Is the soil safe to grow vegetables in Heyburn?
The federal record around Heyburn is a meaningful one — 488 documented sites, mostly Underground Storage Tanks entries (221), the nearest Underground Storage Tanks record about 0.1 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 I protect my plants from frost in Heyburn?
From about Sep 16 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 16 (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 16. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Heyburn's scale — its 6b band and its 176-day season. Your yard writes its own version of Heyburn'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 Heyburn’s own scale
6 of the readings below were taken at Heyburn's own scale — its own ~176-day season between 28°F freezes, the 1,672 acres it covers and 488 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Heyburn's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Heyburn's own 28°F hard-freeze dates, about Apr 23 and Oct 16 and the ~176-day span between themNOAA 1991–2020 Climate Normals
- 488 documented contamination sites on the federal record near Heyburn, the closest Underground Storage Tanks record about 0.1 miles out from the town centreFederal environmental registers
- Heyburn's boundary and the 1,672 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~176-day seasonGrowable Ground crop-matching engine
- The ecoregion at Heyburn's own centroid, the Snake River PlainUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Heyburn's 1,672 acres read through its county's SSURGO summaryfrom Minidoka County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Minidoka 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 Minidoka County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Heyburn's 1,672 acreswhy one lot differs from the next →
- Which side of Heyburn you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,672 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.1 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 Heyburn-wide figureread your own land →