Codington County, in 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.
Codington County lies within the Coteau des Prairies / Glacial Lakes (Northeastern SD) — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Codington County holds more than one microclimate.
Soils and elevations shift across Codington County, so your frost dates and drainage aren't the county average. 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 Codington County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Codington County — the short answer
Codington County, South Dakota: USDA zone 4b, about 170 days between hard freezes, across 440K acres.
- USDA zone
- 4b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 24
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Oct 11
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~170
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 440K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are county 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 Codington County's average, not your lot's — a low corner or a tree line moves it. Against Codington County's 170-day season, see what your own ground reads.
Heat in Codington County
Across a year, Codington County accumulates about 2,175 growing degree days above 50°F, about 251 fewer than the middle South Dakota county — ahead of 8 of South Dakota’s 66 counties. Degree days are the heat a crop actually gets to work with — more of them is more room to ripen a long-season crop before the freeze closes the window.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Codington County
Across Codington County, the ground is predominantly Mollisols, where Buse, Barnes, and Poinsett are the most extensive named soil series. The soil is generally well drained with a silty clay loam surface. Topsoil pH runs about 6.4–7.6, neutral. Rainfall drains through hydrologic group C soils.
Soil order
Mollisols
Drainage
Well drained
Prime farmland
53%
Hydric soils
12%
Soil still varies lot by lot — soil types explained.
How the ground varies across Codington County
The USDA soil survey maps 62% of Codington County as well drained — but another 34% drains differently: 15% somewhat poorly drained, 6% somewhat excessively drained.
Buse is the most extensive named soil at 11% of mapped acres, then Barnes (10%) and Poinsett (9%).
Which of them your own lot sits on is a parcel question, not a county one. Check your address for the survey at your boundary.
What this means for growing in Codington County
Each reading below is measured for Codington County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Codington County are well drained, in hydrologic group C — ground that drains quickly.
The upside is soil you can work early in spring and roots that never drown; the cost is that fast-draining ground dries out fast and leaches nutrients away before plants can use them.
Work in compost and mulch to hold moisture and feed, and water more often in short doses than deep and rarely.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Codington County runs about pH 6.4–7.6, close to neutral.
This is the range most vegetables prefer — one correction you probably do not have to make, which is genuinely good news for a new bed.
Keep it there with compost rather than lime or sulfur, and only amend if your own soil test says otherwise.
USDA NRCS SSURGO
Season length
MeasuredCodington County runs about 170 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
MeasuredCodington County 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 Codington County is in
Codington County sits in the Northern Glaciated Plains — EPA Level III, inside the wider Great Plains. One consistent ecological setting across the whole county.
What Grows in Codington County
We scored all 1,086 plants against Codington County's own USDA zone 4b and its own 170-day season between hard freezes, using the same matching engine that runs a full parcel report. These cleared both. Sun, soil pH and drainage vary lot by lot — those are the parcel questions below. Each card opens that plant's South Dakota profile.
Is it too late to plant in Codington County?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Mar 27; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 24 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 11 — long-season crops need about 90 days of runway, quick greens only 30. Late in the year the fall bench takes over — quick greens, radishes, and garlic that repays you next summer.
Documented around Codington County
- Japanese beetle1 documented records
- monarch butterfly42 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Codington County
USGS estimates 172,950 lb of Glyphosate on Codington County farmland in 2019, its largest by weight, ahead of Metolachlor & Metolachlor-s (63,174 lb) and Metolachlor-s (59,051 lb).
Farmland across the whole county, not any one lot. Check your address for the site-by-site record.
Safe to Grow Here?
What the federal record shows across Codington County — and how to grow with it.
We checked the federal record across Codington County — 347 documented sites across 6 of the 9 source types we track.
The most significant on record: 1 Superfund site (none NPL-listed). Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
There's a meaningful federal record across Codington County — worth a look before you plant food, not a reason to hold back from growing. Proximity to a documented site is information, not a diagnosis of any one yard. A soil test before new food beds is the sensible precaution here, and the map shows exactly which sites sit where, so you can see what's actually near you.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Codington County
Closest first, across Codington County. Listing isn't leaking, and distance isn't exposure.
- 117N53W14BAABNitrate · 2.3 mi
- 117N53W 2DDDCNitrate · 2.5 mi
- 117N53W19AACBNitrate · 2.9 mi
- TEREX SOUTH DAKOTAToxics Release Inventory · 3.1 mi
- WESTERN MACHININGBrownfields · 3.2 mi
- TWIN CITY DIE CASTINGS CO - WATERTOWN DIVToxics Release Inventory · 3.2 mi
- SMITH EQUIPMENT MANUFACTURINGToxics Release Inventory · 3.3 mi
- SMITH EQUIPMENT MANUFACTURINGBrownfields · 3.3 mi
- DYNAMIC ENGINEERING INC.Brownfields · 3.3 mi
- MOFFATT INC.Brownfields · 3.3 mi
- 117N53W12CDDDNitrate · 3.3 mi
- OEM WORLDWIDE LLCBrownfields · 3.3 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Codington County'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 Codington County.
Total Sites
347
across Codington County
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
across Codington County
Severity Distribution
across Codington County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Codington County, two things run higher than the national average across Codington County — Nitrate (124 sites) and Toxics Release Inventory (26 sites). 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.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Check your specific parcel in Codington County
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 Codington County average
Your land is one point inside Codington County
Everything above resolves to Codington County as a whole — one PHZM band and one county frost record, read across 440K 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 county 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 county average.
Your Lot vs the Codington County Average
Codington County Average
- ●USDA Zones 4b, averaged across Codington County
- ●One soil character for all of Codington County
- ●Frost dates read at Codington County's scale: Apr 24 to Oct 11
YOUR Parcel
- ✓Your exact zone, not Codington County's 4b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Codington County
Pull a site-specific report for your exact address in Codington County, South Dakota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Codington County averages can't show:
We read public map data around Codington County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Codington County average
How we know this about Codington County
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at county grain; hard-freeze dates from NOAA 1991–2020 28°F normals at this county’s own record where one resolves, and the labelled statewide window where none does; soils from the USDA NRCS SSURGO survey, area-weighted across the county’s own map units; boundaries and acreage from US Census TIGER/Line 2025; the contamination and pesticide records from the federal sources named in their beats above. Where Codington County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Codington County
When does frost risk typically end in Codington County?
The last hard freeze (28°F) in Codington County typically lands around Apr 24, 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 15.
How long is the growing season in Codington County?
Measured between 28°F hard freezes, Codington County sees about 170 frost-free days — roughly Apr 24 through Oct 11, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 15 to Sep 27, about 135 days.
Is the soil safe to grow vegetables in Codington County?
The federal record around Codington County is a meaningful one — 347 documented sites, mostly Nitrate entries (124), the nearest Nitrate record about 2.3 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.
Everything above is measured at Codington County's scale — its 4b band and its 170-day season. Your yard writes its own version of Codington County's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads South Dakota's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Codington County’s own scale
9 of the readings below were taken at Codington County's own scale — its own ~170-day span between 28°F freezes, the 3 most extensive soil series mapped here and 347 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Codington County's own USDA hardiness band, zones 4bUSDA PHZM 2023
- Codington County's own 28°F hard-freeze dates and its ~170-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Codington CountyUSDA NRCS SSURGO
- 347 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Nitrate record about 2.3 miles outFederal environmental registers
- Codington County's boundary and the 440,054 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4b and a ~170-day seasonGrowable Ground crop-matching engine
- Codington County sitting wholly inside the Northern Glaciated PlainsUS EPA Level III Ecoregions
- Open occurrence records documented in Codington County for 2 tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Codington County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every South Dakota grower plans around — written at state scale, so they stay on the state guidefrom South Dakota
What this page can’t tell you
- How the season shifts across Codington County — the ~170 days above is one reading at its centre; the 12 towns below each carry their owntowns in this county →
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Codington County's 440,054 acreswhy one lot differs from the next →
- Which of those 347 documented sites actually reaches your soil — that needs your address, the wind, and the groundwater directionhow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — none of it survives being averaged over Codington Countyread your own land →