De Smet, South Dakota, sits in USDA hardiness zone 4b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Expect cabbage, cranberry, turkish rocket, and collard greens to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Even in De Smet, 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 De Smet 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 De Smet — soil, climate, flood, and parcel records. How we handle your address.
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De Smet — the short answer
De Smet, South Dakota: USDA zone 4b, about 173 days between hard freezes, across 741 acres of city.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 22
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 12
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~173
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 741 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 De Smet's average, not your lot's — a low corner or a tree line moves it. Against De Smet's 173-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in De Smet
Each reading below is measured for De Smet itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredDe Smet runs about 173 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
MeasuredDe Smet 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 De Smet is in
De Smet sits in the Northern Glaciated Plains — EPA Level III, inside the wider Great Plains. That is read at De Smet's own centroid rather than borrowed from Kingsbury County.
What Grows in De Smet
Every plant below cleared De Smet's own zone 4b and its 173-day season. Each card opens that plant's South Dakota profile. How we score.
Is it too late to plant in De Smet?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Mar 25; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 22 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 12 — long-season crops need about 90 days of runway, quick greens only 30. Even past midsummer there is room for a true fall garden here, and garlic planted near the close carries the momentum into next year.
What's on the federal record near De Smet
Closest first, within ~10 miles of De Smet. Listing isn't leaking, and distance isn't exposure.
- LUBRICATION TECHNOLOGIES LIQUID RECYCLINGBrownfields · 100 ft
- RICH'S GAS & SERVICEUnderground Storage Tanks · 300 ft
- GARY AKKERMANUnderground Storage Tanks · 400 ft
- C & L MINI STOPUnderground Storage Tanks · 400 ft
- MIDSTATE AGRONOMYBrownfields · 700 ft
- 111N56W28DDAANitrate · 700 ft
- 111N56W28DDAA (2)Nitrate · 750 ft
- MAIN STOPUnderground Storage Tanks · 950 ft
- MYERS STANDARDUnderground Storage Tanks · 950 ft
- COWBOY COUNTRY STORE #7Underground Storage Tanks · 950 ft
- DIXON OIL RECYCLING, INC.Brownfields · 1100 ft
- DE SMET SCHOOL DISTRICT #38-2Brownfields · 1300 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from De Smet'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 De Smet.
Total Sites
100
within ~10 miles of De Smet
Risk Level
Moderate
Highest-severity
1 Toxics Release Inventory facility
Sources Checked
within ~10 miles of De Smet
Severity Distribution
within ~10 miles of De Smet
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around De Smet, Nitrate runs higher than the national average — 72 sites within ~10 miles of De Smet. 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 De Smet
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 De Smet average
Your land is one point inside De Smet
Everything above resolves to De Smet as a whole — one PHZM band and one 28°F frost record, read across 741 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 De Smet Average
De Smet Average
- ●USDA Zones 4b, averaged across De Smet
- ●One soil character for all of De Smet
- ●Frost dates read at De Smet's scale: Apr 22 to Oct 12
YOUR Parcel
- ✓Your exact zone, not De Smet's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in De Smet
Pull a site-specific report for your exact address in De Smet, South Dakota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that De Smet averages can't show:
We read public map data around De Smet — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the De Smet average
How we know this about De Smet
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 De Smet’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 De Smet
When does frost risk typically end in De Smet?
The last hard freeze (28°F) in De Smet typically lands around Apr 22, 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 13.
When is the first frost in De Smet?
The first hard freeze (28°F) in De Smet typically arrives around Oct 12, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 28, so the watching starts about Sep 12 — about 173 days after the spring freeze cleared.
How long is the growing season in De Smet?
Measured between 28°F hard freezes, De Smet sees about 173 frost-free days — roughly Apr 22 through Oct 12, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 13 to Sep 28, about 138 days.
Is the soil safe to grow vegetables in De Smet?
The federal record around De Smet shows 100 documented sites, mostly Nitrate entries (72), the nearest Brownfields record under a tenth of a mile out — a typical footprint for a growing area, and proximity to a documented site is information, not a diagnosis of any one yard. It's worth seeing which recorded sites sit closest to where you grow, and testing the soil before new food beds near any of them.
How do I protect my plants from frost in De Smet?
From about Sep 12 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 12 (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 12. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at De Smet's scale — its 4b band and its 173-day season. Your yard writes its own version of De Smet'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 De Smet’s own scale
6 of the readings below were taken at De Smet's own scale — its own ~173-day season between 28°F freezes, the 741 acres it covers and 100 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- De Smet's own USDA hardiness band, zones 4bUSDA PHZM 2023
- De Smet's own 28°F hard-freeze dates, about Apr 22 and Oct 12 and the ~173-day span between themNOAA 1991–2020 Climate Normals
- 100 documented contamination sites on the federal record near De Smet, the closest Brownfields record under a tenth of a mile out from the town centreFederal environmental registers
- De Smet's boundary and the 741 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~173-day seasonGrowable Ground crop-matching engine
- The ecoregion at De Smet's own centroid, the Northern Glaciated PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so De Smet's 741 acres read through its county's SSURGO summaryfrom Kingsbury County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Kingsbury 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 Kingsbury County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among De Smet's 741 acreswhy one lot differs from the next →
- Which side of De Smet you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 741 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields 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 De Smet-wide figureread your own land →
More in South Dakota
Wider growing context
What grows across South DakotaDe Smet sits outside our named growing regions, so South Dakota as a whole is its closest context here.
Nearby growing guides