Hill City, South Dakota, sits in USDA hardiness zone 4b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Expect cabbage, cranberry, cilantro, and collard greens to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Even in Hill City, 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 Hill City 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 Hill City — soil, climate, flood, and parcel records. How we handle your address.
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Hill City — the short answer
Hill City, South Dakota: USDA zone 4b, about 139 days between hard freezes, across 840 acres of city.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 13
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Sep 29
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~139
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 840 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 4b is Hill City's average, not your lot's — a low corner or a tree line moves it. Against Hill City's 139-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Hill City
Each reading below is measured for Hill City itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredHill City runs about 139 days between hard freezes — 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
MeasuredHill City sits in USDA hardiness zone 4b.
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 Hill City is in
Hill City sits in the Middle Rockies — EPA Level III, inside the wider Northwestern Forested Mountains. That is read at Hill City's own centroid, and it is not what its county reads: Pennington County is mostly Northwestern Great Plains. The wider page above you is answering a different question about different ground.
What Grows in Hill City
Every plant below cleared Hill City's own zone 4b and its 139-day season. Each card opens that plant's South Dakota profile. How we score.
Is it too late to plant in Hill City?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Apr 15; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 13 (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. In a season this compact, fast finishers and cold-hardy greens do the late work, and garlic tucked in before the freeze repays you next summer.
What's on the federal record near Hill City
Closest first, within ~10 miles of Hill City. Listing isn't leaking, and distance isn't exposure.
- 001S05E30Nitrate · 800 ft
- PENNINGTON COUNTY HWY DEPTUnderground Storage Tanks · 1100 ft
- BLACK HILLS CENTRAL RAILROADBrownfields · 1500 ft
- 001S05E30DABDNitrate · 1600 ft
- BOB'S SERVICEUnderground Storage Tanks · 1700 ft
- H & H MARKETUnderground Storage Tanks · 1700 ft
- IRON HORSE CONOCOUnderground Storage Tanks · 1700 ft
- HEART OF THE HILLS CONVENIENCE STOREUnderground Storage Tanks · 1900 ft
- 001S05E30CCDDNitrate · 2300 ft
- HEART OF THE WESTUnderground Storage Tanks · 0.6 mi
- Mohawk Tin MineMining · 0.6 mi
- 001S05E30BDDDNitrate · 0.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Hill City'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 Hill City.
Total Sites
132
within ~10 miles of Hill City
Risk Level
Elevated
Highest-severity
3 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Hill City
Severity Distribution
within ~10 miles of Hill City
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Hill City, two things run higher than the national average within ~10 miles of Hill City — Mining (64 sites) and Nitrate (40 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
Mining: Mining sites — both historic and active — can leach heavy metals (arsenic, lead, cadmium, mercury) into soil and water for centuries after operations cease.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Hill City
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 Hill City average
Your land is one point inside Hill City
Everything above resolves to Hill City as a whole — one PHZM band and one 28°F frost record, read across 840 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 Hill City Average
Hill City Average
- ●USDA Zones 4b, averaged across Hill City
- ●One soil character for all of Hill City
- ●Frost dates read at Hill City's scale: May 13 to Sep 29
YOUR Parcel
- ✓Your exact zone, not Hill City's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Hill City
Pull a site-specific report for your exact address in Hill City, South Dakota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Hill City averages can't show:
We read public map data around Hill City — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Hill City average
How we know this about Hill City
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 Hill City’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 Hill City
When does frost risk typically end in Hill City?
The last hard freeze (28°F) in Hill City typically lands around May 13, 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 Jun 3.
When is the first frost in Hill City?
The first hard freeze (28°F) in Hill City 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 139 days after the spring freeze cleared.
How long is the growing season in Hill City?
Measured between 28°F hard freezes, Hill City sees about 139 frost-free days — roughly May 13 through Sep 29, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Jun 3 to Sep 15, about 104 days.
Is the soil safe to grow vegetables in Hill City?
The federal record around Hill City is a meaningful one — 132 documented sites, mostly Mining entries (64), the nearest Nitrate 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 gardeners stretch the season in Hill City?
With about 139 frost-free days between hard freezes, Hill City 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 167 to 195 days — and cold frames or low tunnels buy more. Starting transplants indoors ahead of the May 13 hard-freeze normal stretches the season without touching the calendar.
Everything above is measured at Hill City's scale — its 4b band and its 139-day season. Your yard writes its own version of Hill City'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 Hill City’s own scale
6 of the readings below were taken at Hill City's own scale — its own ~139-day season between 28°F freezes, the 840 acres it covers and 132 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Hill City's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Hill City's own 28°F hard-freeze dates, about May 13 and Sep 29 and the ~139-day span between themNOAA 1991–2020 Climate Normals
- 132 documented contamination sites on the federal record near Hill City, the closest Nitrate record about 0.2 miles out from the town centreFederal environmental registers
- Hill City's boundary and the 840 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~139-day seasonGrowable Ground crop-matching engine
- Hill City sits in the Middle Rockies — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Hill City's 840 acres read through its county's SSURGO summaryfrom Pennington County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Pennington County
- The growing challenges every South Dakota grower plans around — written at state scale, so they stay on the state guidefrom South Dakota
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Pennington County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Hill City's 840 acreswhy one lot differs from the next →
- Which side of Hill City you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 840 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate 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 Hill City-wide figureread your own land →
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