Grassland Colony, South Dakota, sits in USDA hardiness zone 4b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
The conditions favor cabbage, cranberry, turkish rocket, and collard greens, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in Grassland Colony, 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 Grassland Colony 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 Grassland Colony — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Grassland Colony — the short answer
Grassland Colony, South Dakota: USDA zone 4b, about 163 days between hard freezes, across 273 acres of town.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 29
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 9
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~163
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 273 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 Grassland Colony's average, not your lot's — a low corner or a tree line moves it. Against Grassland Colony's 163-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Grassland Colony
Each reading below is measured for Grassland Colony itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredGrassland Colony runs about 163 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
MeasuredGrassland Colony 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 Grassland Colony is in
Grassland Colony sits in the Northern Glaciated Plains — EPA Level III, inside the wider Great Plains. That is read at Grassland Colony's own centroid, and it is not what its county reads: McPherson County is mostly Northwestern Glaciated Plains. The wider page above you is answering a different question about different ground.
What Grows in Grassland Colony
Every plant below cleared Grassland Colony's own zone 4b and its 163-day season. Each card opens that plant's South Dakota profile. How we score.
Is it too late to plant in Grassland Colony?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Apr 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 29 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 9 — long-season crops need about 90 days of runway, quick greens only 30. The tail of the season still works: sixty-day crops into late summer, quick greens after, garlic last of all.
What's on the federal record near Grassland Colony
Closest first, within ~10 miles of Grassland Colony. Listing isn't leaking, and distance isn't exposure.
- 125N66W23ABAANitrate · 3.2 mi
- 125N66W22DADCNitrate · 3.3 mi
- MIDLAND CAMPUSUnderground Storage Tanks · 5.8 mi
- FASHION CLEANERSUnderground Storage Tanks · 6.7 mi
- LEOLA SCHOOL DIST 44-2Underground Storage Tanks · 7.7 mi
- 126N67W17DAADNitrate · 7.7 mi
- 125N67W32AAAANitrate · 7.7 mi
- 126N67W17DCDCNitrate · 7.8 mi
- FORMER IMPLEMENT DEALERUnderground Storage Tanks · 7.8 mi
- AGTEGRAUnderground Storage Tanks · 7.8 mi
- 126N67W17CDDA3Nitrate · 7.9 mi
- 126N67W17CDDANitrate · 8.0 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Grassland Colony'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 Grassland Colony.
Sources Checked
within ~10 miles of Grassland Colony
Severity Distribution
within ~10 miles of Grassland Colony
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Grassland Colony, Nitrate runs higher than the national average — 20 sites within ~10 miles of Grassland Colony. 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 Grassland Colony
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 Grassland Colony average
Your land is one point inside Grassland Colony
Everything above resolves to Grassland Colony as a whole — one PHZM band and one 28°F frost record, read across 273 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 Grassland Colony Average
Grassland Colony Average
- ●USDA Zones 4b, averaged across Grassland Colony
- ●One soil character for all of Grassland Colony
- ●Frost dates read at Grassland Colony's scale: Apr 29 to Oct 9
YOUR Parcel
- ✓Your exact zone, not Grassland Colony's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Grassland Colony
Pull a site-specific report for your exact address in Grassland Colony, South Dakota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Grassland Colony averages can't show:
We read public map data around Grassland Colony — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Grassland Colony average
How we know this about Grassland Colony
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 Grassland Colony’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 Grassland Colony
When does frost risk typically end in Grassland Colony?
The last hard freeze (28°F) in Grassland Colony typically lands around Apr 29, 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 20.
When is the first frost in Grassland Colony?
The first hard freeze (28°F) in Grassland Colony typically arrives around Oct 9, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 25, so the watching starts about Sep 9 — about 163 days after the spring freeze cleared.
How long is the growing season in Grassland Colony?
Measured between 28°F hard freezes, Grassland Colony sees about 163 frost-free days — roughly Apr 29 through Oct 9, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 20 to Sep 25, about 128 days.
Is the soil safe to grow vegetables in Grassland Colony?
The federal record around Grassland Colony is light — 29 documented sites across the 9 federal source types we checked, mostly Nitrate entries (20), the nearest Nitrate record about 3.2 miles out — and proximity to a documented site is information, not a diagnosis of any one yard. Growing food here starts from a strong position; a soil test before new food beds settles any site-specific question.
How do I protect my plants from frost in Grassland Colony?
From about Sep 9 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 9 (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 9. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Grassland Colony's scale — its 4b band and its 163-day season. Your yard writes its own version of Grassland Colony'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 Grassland Colony’s own scale
6 of the readings below were taken at Grassland Colony's own scale — its own ~163-day season between 28°F freezes, the 273 acres it covers and 29 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Grassland Colony's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Grassland Colony's own 28°F hard-freeze dates, about Apr 29 and Oct 9 and the ~163-day span between themNOAA 1991–2020 Climate Normals
- 29 documented contamination sites on the federal record near Grassland Colony, the closest Nitrate record about 3.2 miles out from the town centreFederal environmental registers
- Grassland Colony's boundary and the 273 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~163-day seasonGrowable Ground crop-matching engine
- Grassland Colony 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 Grassland Colony's 273 acres read through its county's SSURGO summaryfrom McPherson County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom McPherson 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 McPherson County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Grassland Colony's 273 acreswhy one lot differs from the next →
- Which side of Grassland Colony you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 273 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 3.2 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 Grassland Colony-wide figureread your own land →
More in South Dakota
Wider growing context
What grows across South DakotaGrassland Colony sits outside our named growing regions, so South Dakota as a whole is its closest context here.
Nearby growing guides