Altamont, Illinois, 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.
Well-matched crops include cabbage, hazelnut, lavender, and collard greens, and the gap between "grows in the area" and "grows in your yard" is closed by soil, sun, and drainage.
Even in Altamont, 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 Altamont 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 Altamont — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Altamont — the short answer
Altamont, Illinois: USDA zone 6b, about 214 days between hard freezes, across 984 acres of city.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 1
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 1
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~214
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 984 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 Altamont's average, not your lot's — a low corner or a tree line moves it. Against Altamont's 214-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Altamont
Each reading below is measured for Altamont itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredAltamont runs about 214 days between hard freezes — a long growing season.
There is slack for succession plantings and slow-finishing crops: many vegetables can be sown twice, and the heat-lovers have time to ripen fully.
Plan a second sowing of quick crops after the first comes out, and use the fall window most gardeners let sit idle.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredAltamont 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 Altamont is in
Altamont sits in the Interior River Valleys and Hills — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Altamont's own centroid rather than borrowed from Effingham County.
What Grows in Altamont
Every plant below cleared Altamont's own zone 6b and its 214-day season. Each card opens that plant's Illinois profile. How we score.
Is it too late to plant in Altamont?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Mar 4; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 1 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 1 — long-season crops need about 90 days of runway, quick greens only 30. With a season this long, “too late” mostly means “switch crops” — second sowings and a full fall garden are the norm, with garlic closing the year.
What's on the federal record near Altamont
Closest first, within ~10 miles of Altamont. Listing isn't leaking, and distance isn't exposure.
- Casey's General StoreUnderground Storage Tanks · 200 ft
- Pioneer Oil CompanyUnderground Storage Tanks · 300 ft
- Continental TelephoneUnderground Storage Tanks · 350 ft
- Jumpin Jimmy'sUnderground Storage Tanks · 600 ft
- A&H IMPLEMENTBrownfields · 1000 ft
- A & H ImplementUnderground Storage Tanks · 1000 ft
- David W. FrederkingUnderground Storage Tanks · 1200 ft
- Township of SummitUnderground Storage Tanks · 1200 ft
- ALLISONS FURNITURE RESTORATIONBrownfields · 1200 ft
- Altamont Whoesale CoUnderground Storage Tanks · 1800 ft
- Altamont Comm Unit School #10Underground Storage Tanks · 1900 ft
- R&H Plumbing & HeatingUnderground Storage Tanks · 2000 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Altamont'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 Altamont.
Total Sites
90
within ~10 miles of Altamont
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Altamont
Severity Distribution
within ~10 miles of Altamont
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Altamont, Underground Storage Tanks runs higher than the national average — 58 sites within ~10 miles of Altamont. That's not a problem with your land — it's information about it.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Altamont
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 Altamont average
Your land is one point inside Altamont
Everything above resolves to Altamont as a whole — one PHZM band and one 28°F frost record, read across 984 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 Altamont Average
Altamont Average
- ●USDA Zones 6b, averaged across Altamont
- ●One soil character for all of Altamont
- ●Frost dates read at Altamont's scale: Apr 1 to Nov 1
YOUR Parcel
- ✓Your exact zone, not Altamont's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Altamont
Pull a site-specific report for your exact address in Altamont, Illinois — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Altamont averages can't show:
We read public map data around Altamont — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Altamont average
How we know this about Altamont
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 Altamont’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 Altamont
When does frost risk typically end in Altamont?
The last hard freeze (28°F) in Altamont typically lands around Apr 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 Apr 22.
When is the first frost in Altamont?
The first hard freeze (28°F) in Altamont typically arrives around Nov 1, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 18, so the watching starts about Oct 2 — about 214 days after the spring freeze cleared.
How long is the growing season in Altamont?
Measured between 28°F hard freezes, Altamont sees about 214 frost-free days — roughly Apr 1 through Nov 1, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 22 to Oct 18, about 179 days.
Is the soil safe to grow vegetables in Altamont?
The federal record around Altamont is a meaningful one — 90 documented sites, mostly Underground Storage Tanks entries (58), 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 Altamont?
From about Oct 2 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 Nov 1 (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 Nov 1. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Altamont's scale — its 6b band and its 214-day season. Your yard writes its own version of Altamont'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 Altamont’s own scale
6 of the readings below were taken at Altamont's own scale — its own ~214-day season between 28°F freezes, the 984 acres it covers and 90 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Altamont's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Altamont's own 28°F hard-freeze dates, about Apr 1 and Nov 1 and the ~214-day span between themNOAA 1991–2020 Climate Normals
- 90 documented contamination sites on the federal record near Altamont, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Altamont's boundary and the 984 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~214-day seasonGrowable Ground crop-matching engine
- The ecoregion at Altamont's own centroid, the Interior River Valleys and HillsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Altamont's 984 acres read through its county's SSURGO summaryfrom Effingham County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Effingham County
- The growing challenges every Illinois grower plans around — written at state scale, so they stay on the state guidefrom Illinois
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Effingham County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Altamont's 984 acreswhy one lot differs from the next →
- Which side of Altamont you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 984 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 Altamont-wide figureread your own land →
More in Illinois
Wider growing context
What grows across IllinoisAltamont sits outside our named growing regions, so Illinois as a whole is its closest context here.
Nearby growing guides