Olmsted, Illinois, sits in USDA hardiness zone 7a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
A short list that earns its place here — cabbage, hazelnut, california poppy, and collard greens — with any one site's soil, sun, and drainage making the final cut.
Even in Olmsted, 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 Olmsted 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 Olmsted — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Olmsted — the short answer
Olmsted, Illinois: USDA zone 7a, about 244 days between hard freezes, across 2K acres of town.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 19
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 18
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~244
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town 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 7a is Olmsted's average, not your lot's — a low corner or a tree line moves it. Against Olmsted's 244-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Olmsted
Each reading below is measured for Olmsted itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredOlmsted runs about 244 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
MeasuredOlmsted sits in USDA hardiness zone 7a.
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 Olmsted is in
Olmsted sits in the Interior River Valleys and Hills — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Olmsted's own centroid rather than borrowed from Pulaski County.
What Grows in Olmsted
Every plant below cleared Olmsted's own zone 7a and its 244-day season. Each card opens that plant's Illinois profile. How we score.
Is it too late to plant in Olmsted?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 19; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 19 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 18 — long-season crops need about 90 days of runway, quick greens only 30. Here the season winds down slowly: late sowings, a real autumn harvest, and garlic in the ground before the first hard freeze.
What's on the federal record near Olmsted
Closest first, within ~10 miles of Olmsted. Listing isn't leaking, and distance isn't exposure.
- Schwieger BrosincUnderground Storage Tanks · 800 ft
- Country CafeUnderground Storage Tanks · 800 ft
- GOLDEN CAT/DIV. OF RALSTON PURINA CO.Brownfields · 1400 ft
- Olmsted Automotive ServiceUnderground Storage Tanks · 1700 ft
- 15S 1E-22.5a1Nitrate · 1900 ft
- 15S 1E-22.4a1Nitrate · 1900 ft
- Lowe Southern Clay IncUnderground Storage Tanks · 0.6 mi
- Golden Cat Division of Ralston PurinaUnderground Storage Tanks · 0.6 mi
- AFCOBrownfields · 0.9 mi
- Fill-Up MartUnderground Storage Tanks · 1.0 mi
- Olmsted Locks & DamUnderground Storage Tanks · 1.2 mi
- Bishop Burd ConstructionUnderground Storage Tanks · 1.3 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Olmsted'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 Olmsted.
Total Sites
143
within ~10 miles of Olmsted
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Olmsted
Severity Distribution
within ~10 miles of Olmsted
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Olmsted, Nitrate runs higher than the national average — 56 sites within ~10 miles of Olmsted. That's not a problem with your land — it's information about it.
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 Olmsted
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 Olmsted average
Your land is one point inside Olmsted
Everything above resolves to Olmsted 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 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 Olmsted Average
Olmsted Average
- ●USDA Zones 7a, averaged across Olmsted
- ●One soil character for all of Olmsted
- ●Frost dates read at Olmsted's scale: Mar 19 to Nov 18
YOUR Parcel
- ✓Your exact zone, not Olmsted's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Olmsted
Pull a site-specific report for your exact address in Olmsted, Illinois — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Olmsted averages can't show:
We read public map data around Olmsted — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Olmsted average
How we know this about Olmsted
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 Olmsted’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 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 Olmsted
When does frost risk typically end in Olmsted?
The last hard freeze (28°F) in Olmsted typically lands around Mar 19, 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 9.
When is the first frost in Olmsted?
The first hard freeze (28°F) in Olmsted typically arrives around Nov 18, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 4, so the watching starts about Oct 19 — about 244 days after the spring freeze cleared.
How long is the growing season in Olmsted?
Measured between 28°F hard freezes, Olmsted sees about 244 frost-free days — roughly Mar 19 through Nov 18, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 9 to Nov 4, about 209 days.
Is the soil safe to grow vegetables in Olmsted?
The federal record around Olmsted is a meaningful one — 143 documented sites, mostly Underground Storage Tanks entries (77), the nearest Underground Storage Tanks record about 0.2 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 Olmsted?
From about Oct 19 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 18 (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 18. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Olmsted's scale — its 7a band and its 244-day season. Your yard writes its own version of Olmsted'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 Olmsted’s own scale
6 of the readings below were taken at Olmsted's own scale — its own ~244-day season between 28°F freezes, the 2,154 acres it covers and 143 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Olmsted's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Olmsted's own 28°F hard-freeze dates, about Mar 19 and Nov 18 and the ~244-day span between themNOAA 1991–2020 Climate Normals
- 143 documented contamination sites on the federal record near Olmsted, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Olmsted's boundary and the 2,154 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~244-day seasonGrowable Ground crop-matching engine
- The ecoregion at Olmsted'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 Olmsted's 2,154 acres read through its county's SSURGO summaryfrom Pulaski County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Pulaski 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 Pulaski County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Olmsted's 2,154 acreswhy one lot differs from the next →
- Which side of Olmsted you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,154 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.2 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 Olmsted-wide figureread your own land →