Grenville, South Dakota, sits in USDA hardiness zone 4b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Reliable performers under these conditions include cabbage, cranberry, turkish rocket, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Grenville, 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 Grenville 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 Grenville — soil, climate, flood, and parcel records. How we handle your address.
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Grenville — the short answer
Grenville, South Dakota: USDA zone 4b, about 179 days between hard freezes, across 152 acres of town.
- 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 18
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~179
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 152 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 Grenville's average, not your lot's — a low corner or a tree line moves it. Against Grenville's 179-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Grenville
Each reading below is measured for Grenville itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredGrenville runs about 179 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
MeasuredGrenville 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 Grenville is in
Grenville sits in the Northern Glaciated Plains — EPA Level III, inside the wider Great Plains. That is read at Grenville's own centroid rather than borrowed from Day County.
What Grows in Grenville
Every plant below cleared Grenville's own zone 4b and its 179-day season. Each card opens that plant's South Dakota profile. How we score.
Is it too late to plant in Grenville?
Rarely: the season closes in stages, not all at once, and each stage has its crops. 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 18 — 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 Grenville
Closest first, within ~10 miles of Grenville. Listing isn't leaking, and distance isn't exposure.
- GRENVILLE SPORTS MARTUnderground Storage Tanks · 950 ft
- WAUBAY NTL WILDLIFE REFUGEUnderground Storage Tanks · 4.1 mi
- 122N55W 2CCBDNitrate · 4.6 mi
- 124N55W32CBBDNitrate · 4.6 mi
- 124N53W20DADC RNitrate · 4.6 mi
- 123N53W 9DADC RNitrate · 5.0 mi
- DAY COUNTY HWY DEPTUnderground Storage Tanks · 5.2 mi
- 123N56W 1ADACNitrate · 5.2 mi
- HANKS OIL COUnderground Storage Tanks · 5.3 mi
- 123N56W 1ADBDNitrate · 5.4 mi
- 123N56W 1ADBBNitrate · 5.4 mi
- COMMUNITY OIL CO. OF DAY COUNTYUnderground Storage Tanks · 5.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Grenville'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 Grenville.
Sources Checked
within ~10 miles of Grenville
Severity Distribution
within ~10 miles of Grenville
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Grenville, Nitrate runs higher than the national average — 72 sites within ~10 miles of Grenville. 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 Grenville
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 Grenville average
Your land is one point inside Grenville
Everything above resolves to Grenville as a whole — one PHZM band and one 28°F frost record, read across 152 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 Grenville Average
Grenville Average
- ●USDA Zones 4b, averaged across Grenville
- ●One soil character for all of Grenville
- ●Frost dates read at Grenville's scale: Apr 22 to Oct 18
YOUR Parcel
- ✓Your exact zone, not Grenville's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Grenville
Pull a site-specific report for your exact address in Grenville, South Dakota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Grenville averages can't show:
We read public map data around Grenville — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Grenville average
How we know this about Grenville
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 Grenville’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 Grenville
When does frost risk typically end in Grenville?
The last hard freeze (28°F) in Grenville 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 Grenville?
The first hard freeze (28°F) in Grenville typically arrives around Oct 18, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 4, so the watching starts about Sep 18 — about 179 days after the spring freeze cleared.
How long is the growing season in Grenville?
Measured between 28°F hard freezes, Grenville sees about 179 frost-free days — roughly Apr 22 through Oct 18, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 13 to Oct 4, about 144 days.
Is the soil safe to grow vegetables in Grenville?
The federal record around Grenville shows 81 documented sites, mostly Nitrate entries (72), the nearest Underground Storage Tanks record about 0.2 miles 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 Grenville?
From about Sep 18 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 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 Oct 18. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Grenville's scale — its 4b band and its 179-day season. Your yard writes its own version of Grenville'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 Grenville’s own scale
6 of the readings below were taken at Grenville's own scale — its own ~179-day season between 28°F freezes, the 152 acres it covers and 81 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Grenville's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Grenville's own 28°F hard-freeze dates, about Apr 22 and Oct 18 and the ~179-day span between themNOAA 1991–2020 Climate Normals
- 81 documented contamination sites on the federal record near Grenville, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Grenville's boundary and the 152 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~179-day seasonGrowable Ground crop-matching engine
- The ecoregion at Grenville's own centroid, the Northern Glaciated PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Grenville's 152 acres read through its county's SSURGO summaryfrom Day County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Day 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 Day County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Grenville's 152 acreswhy one lot differs from the next →
- Which side of Grenville you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 152 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 Grenville-wide figureread your own land →