Plankinton, South Dakota, sits in USDA hardiness zone 5a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Reliable performers under these conditions include cabbage, cranberry, lavender, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Plankinton, 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 Plankinton 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 Plankinton — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Plankinton — the short answer
Plankinton, South Dakota: USDA zone 5a, about 178 days between hard freezes, across 488 acres of city.
- USDA zone
- 5a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 21
- 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
- ~178
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 488 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 5a is Plankinton's average, not your lot's — a low corner or a tree line moves it. Against Plankinton's 178-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Plankinton
Each reading below is measured for Plankinton itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredPlankinton runs about 178 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
MeasuredPlankinton sits in USDA hardiness zone 5a.
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 Plankinton is in
Plankinton sits in the Northern Glaciated Plains — EPA Level III, inside the wider Great Plains. That is read at Plankinton's own centroid, and it is not what its county reads: Aurora County is mostly Northwestern Glaciated Plains. The wider page above you is answering a different question about different ground.
What Grows in Plankinton
Every plant below cleared Plankinton's own zone 5a and its 178-day season. Each card opens that plant's South Dakota profile. How we score.
Is it too late to plant in Plankinton?
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 24; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 21 (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. As the window narrows, the plantings just get faster — fall brassicas, then greens, then garlic to finish.
What's on the federal record near Plankinton
Closest first, within ~10 miles of Plankinton. Listing isn't leaking, and distance isn't exposure.
- HOWARDS SERVICEUnderground Storage Tanks · 150 ft
- 103N64W15DCDDNitrate · 750 ft
- GUINDON SERVICEUnderground Storage Tanks · 950 ft
- AURORA COUNTY HWY DEPTUnderground Storage Tanks · 1200 ft
- 103N64W22ABDCNitrate · 1300 ft
- OVERWEG AUTO, GLASS &FUELUnderground Storage Tanks · 1800 ft
- AJ'S ONE STOP & SERVICEUnderground Storage Tanks · 2000 ft
- SD DEPT OF TRANSPORTATIONUnderground Storage Tanks · 2400 ft
- ROADSIDE 66Underground Storage Tanks · 0.6 mi
- STATE TRAINING SCHOOL FACILITYUnderground Storage Tanks · 1.1 mi
- 103N64W14ADBD (2)Nitrate · 1.2 mi
- COFFEE CUP FUEL STOP #4Underground Storage Tanks · 2.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Plankinton'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 Plankinton.
Total Sites
50
within ~10 miles of Plankinton
Risk Level
Moderate
Highest-severity
40 nitrate monitoring sites
Severity Distribution
within ~10 miles of Plankinton
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Plankinton, Nitrate runs higher than the national average — 40 sites within ~10 miles of Plankinton. 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 Plankinton
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 Plankinton average
Your land is one point inside Plankinton
Everything above resolves to Plankinton as a whole — one PHZM band and one 28°F frost record, read across 488 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 Plankinton Average
Plankinton Average
- ●USDA Zones 5a, averaged across Plankinton
- ●One soil character for all of Plankinton
- ●Frost dates read at Plankinton's scale: Apr 21 to Oct 16
YOUR Parcel
- ✓Your exact zone, not Plankinton's 5a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Plankinton
Pull a site-specific report for your exact address in Plankinton, South Dakota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Plankinton averages can't show:
We read public map data around Plankinton — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Plankinton average
How we know this about Plankinton
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 Plankinton’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 Plankinton
When does frost risk typically end in Plankinton?
The last hard freeze (28°F) in Plankinton typically lands around Apr 21, 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 12.
When is the first frost in Plankinton?
The first hard freeze (28°F) in Plankinton 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 178 days after the spring freeze cleared.
How long is the growing season in Plankinton?
Measured between 28°F hard freezes, Plankinton sees about 178 frost-free days — roughly Apr 21 through Oct 16, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 12 to Oct 2, about 143 days.
Is the soil safe to grow vegetables in Plankinton?
The federal record around Plankinton shows 50 documented sites, mostly Nitrate entries (40), the nearest Underground Storage Tanks 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 Plankinton?
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 Plankinton's scale — its 5a band and its 178-day season. Your yard writes its own version of Plankinton'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 Plankinton’s own scale
6 of the readings below were taken at Plankinton's own scale — its own ~178-day season between 28°F freezes, the 488 acres it covers and 50 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Plankinton's own USDA hardiness band, zones 5aUSDA PHZM 2023
- Plankinton's own 28°F hard-freeze dates, about Apr 21 and Oct 16 and the ~178-day span between themNOAA 1991–2020 Climate Normals
- 50 documented contamination sites on the federal record near Plankinton, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Plankinton's boundary and the 488 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5a and a ~178-day seasonGrowable Ground crop-matching engine
- Plankinton sits in the Northern Glaciated Plains — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Plankinton's 488 acres read through its county's SSURGO summaryfrom Aurora County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Aurora 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 Aurora County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Plankinton's 488 acreswhy one lot differs from the next →
- Which side of Plankinton you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 488 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 Plankinton-wide figureread your own land →
More in South Dakota
Wider growing context
What grows across South DakotaPlankinton sits outside our named growing regions, so South Dakota as a whole is its closest context here.
Nearby growing guides