Carthage, South Dakota, sits in USDA hardiness zones 4a-5b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
On paper, tomato, black hills spruce, potato, and rhubarb all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in Carthage, 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 Carthage lot. Enter your address and we'll score 1,112 plants against your land's actual soil, sun, and frost.
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Quick Facts
USDA Zones
4a-5b
Last Hard Freeze (28°F)
Apr 12
Town normal — light frosts run a few weeks later
First Hard Freeze (28°F)
Oct 26
Town normal — light frosts arrive a few weeks earlier
City Area
934 acres
Hardiness Zone Range
Zone maps are averages across Carthage. Your yard's slope, trees, and frost pockets shift what actually grows — see your land's exact reading.
Soil varies lot by lot — soil types explained.
What Grows in Carthage
Plants matched to Carthage's USDA zones 4a-5b — each links to its full growing profile.
Is it too late to plant in Carthage?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 15; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 12 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 26 — 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.
Growing Challenges in South Dakota
What an experienced grower plans around here — each one has a move.
Extreme cold and short growing season
Cold-proven varieties and a high tunnel turn a short prairie season into a reliable one — the northern-plains standard.
Low rainfall in western SD
West-river gardens run on drip and mulch — putting the water plan first makes the dry summers routine.
Wind exposure on the open prairie
A windbreak is the best structure you can plant on the prairie — even a shrub row shifts the microclimate.
For cultivar selection, pest pressure, and planting-time guidance specific to South Dakota, the SDSU Extension is the authoritative local source.
Environmental Intelligence
Understanding what's nearby helps you make informed decisions about where and how to grow.
Severity Distribution
within ~10 miles of Carthage
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Carthage, Nitrate runs higher than the national average — 28 sites nearby. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around 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 Carthage
Get exact proximity distances to contamination sources for your specific parcel — plus soil, sun, drainage, and 1,112 plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Your Specific Parcel Matters
Carthage Average
- ●USDA Zones 4a-5b
- ●Generic soil type for the area
- ●State-average frost dates
YOUR Parcel
- ✓Your exact hardiness zone
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Carthage
Pull a site-specific report for your exact address in Carthage, South Dakota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your exact spot that zone averages miss:
We read public map data for this spot — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources analyzed in seconds
Key Growing Facts for Carthage, South Dakota
- USDA Hardiness Zones: 4a-5b (USDA PHZM 2023)
- Last Hard Freeze (28°F): Apr 12 (town normal, NOAA 1991–2020 Climate Normals — light frosts can follow for a few weeks)
- First Hard Freeze (28°F): Oct 26 (town normal, NOAA 1991–2020 Climate Normals — light frosts can arrive a few weeks earlier)
- Days Between Hard Freezes: ~197 (town normal, NOAA 1991–2020 Climate Normals)
- Land Area: 934 acres (US Census TIGER 2025)
Zone data: USDA ARS Plant Hardiness Zone Map 2023. Climate data: NOAA NCEI. Boundaries: US Census TIGER/Line 2025.
Frequently Asked Questions
What hardiness zone is Carthage, South Dakota?
Carthage sits in USDA hardiness zones 4a-5b, per the USDA Plant Hardiness Zone Map 2023. Zones reflect average annual extreme minimum temperatures from 1991–2020 weather data.
Is it too late to plant in Carthage?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 15; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 12 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 26 — 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.
When does frost risk typically end in Carthage?
The last hard freeze (28°F) in Carthage typically lands around Apr 12, per NOAA 1991–2020 climate normals — an earlier marker than the light-frost dates many planting charts quote. That marks the hard freeze, not the last light frost — light frosts can still bite for a few more weeks, so tender transplants usually wait another 2–3 weeks.
When is the first frost in Carthage?
The first hard freeze (28°F) in Carthage typically arrives around Oct 26, per NOAA 1991–2020 climate normals — the point most tender summer crops finish. Lighter frosts usually reach a couple of weeks earlier, so watch the forecast from late summer on and harvest or cover tender plants before the first cold night.
What vegetables grow in Carthage?
Carthage's zones 4a-5b support a wide range — strong performers include Tomato, Black Hills Spruce, Potato, and Rhubarb. What actually takes on any one site comes down to its soil, sun, and drainage, and we score each plant against the real conditions at your address.
Which hardiness zone is Carthage, really?
Officially, Carthage sits in USDA zones 4a-5b (USDA PHZM 2023) — but a zone is a 30-year average of winter's coldest night across an area, and it can't see any one yard. A south-facing slope, a tree line, or a low frost pocket can shift a single site by half a zone either way, which is why neighboring gardeners often quote different numbers. We read the conditions at your exact address — soil, sun, slope, and frost — and score 1,112 plants against what's actually there.
Is the soil safe to grow vegetables in Carthage?
The federal record around Carthage is light — 29 documented sites across the 9 federal source types we checked — 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 Carthage?
As the season closes around the first 28°F hard freeze near Oct 26 (NOAA 1991–2020 climate normals), a few moves buy time: cover tender plants with floating row cover or an old sheet on still, clear nights, water the soil the afternoon before a freeze so it holds warmth overnight, and harvest frost-tender crops like tomatoes, peppers, and basil before the first hard night. Hardy greens and root crops shrug off light frost and often sweeten after it, so leave them in.
Everything on this page is a Carthage average. Your yard writes its own version — we read soil, sun, drainage, and frost at your exact address. Try it for 14 days — no card required.