Oxbow, North Dakota, sits in USDA hardiness zone 4a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Among the crops suited to this profile: cabbage, cranberry, turkish rocket, and collard greens. The site-level story — soil, sun, drainage — decides the rest.
Even in Oxbow, 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 Oxbow 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 Oxbow — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Oxbow — the short answer
Oxbow, North Dakota: USDA zone 4a, about 170 days between hard freezes, across 980 acres of city.
- USDA zone
- 4a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 26
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 13
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~170
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 980 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 4a is Oxbow's average, not your lot's — a low corner or a tree line moves it. Against Oxbow's 170-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Oxbow
Each reading below is measured for Oxbow itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredOxbow 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
MeasuredOxbow sits in USDA hardiness zone 4a.
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 Oxbow is in
Oxbow sits in the Lake Agassiz Plain — EPA Level III, inside the wider Great Plains. That is read at Oxbow's own centroid rather than borrowed from Cass County.
What Grows in Oxbow
Every plant below cleared Oxbow's own zone 4a and its 170-day season. Each card opens that plant's North Dakota profile. How we score.
Is it too late to plant in Oxbow?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Mar 29; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 26 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 13 — 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 Oxbow
Closest first, within ~10 miles of Oxbow. Listing isn't leaking, and distance isn't exposure.
- Horace SupplyUnderground Storage Tanks · 0.5 mi
- 137-049-24BDANitrate · 0.6 mi
- 137-049-22ADBNitrate · 1.2 mi
- 137-049-25CCCNitrate · 1.2 mi
- 137-049-12CDDNitrate · 1.8 mi
- 137N40W31BBC 01Nitrate · 2.1 mi
- 137-049-15BAANitrate · 2.2 mi
- 137-049-28CDDNitrate · 2.8 mi
- 137-049-09DCDNitrate · 2.9 mi
- 180020Nitrate · 2.9 mi
- 137-049-17DAA1Nitrate · 3.2 mi
- NELSON EZ PULLBrownfields · 3.5 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Oxbow'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 Oxbow.
Sources Checked
within ~10 miles of Oxbow
Severity Distribution
within ~10 miles of Oxbow
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Oxbow, Nitrate runs higher than the national average — 106 sites within ~10 miles of Oxbow. 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 Oxbow
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 Oxbow average
Your land is one point inside Oxbow
Everything above resolves to Oxbow as a whole — one PHZM band and one 28°F frost record, read across 980 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 Oxbow Average
Oxbow Average
- ●USDA Zones 4a, averaged across Oxbow
- ●One soil character for all of Oxbow
- ●Frost dates read at Oxbow's scale: Apr 26 to Oct 13
YOUR Parcel
- ✓Your exact zone, not Oxbow's 4a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Oxbow
Pull a site-specific report for your exact address in Oxbow, North Dakota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Oxbow averages can't show:
We read public map data around Oxbow — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Oxbow average
How we know this about Oxbow
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 Oxbow’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 Oxbow
When does frost risk typically end in Oxbow?
The last hard freeze (28°F) in Oxbow typically lands around Apr 26, 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 17.
When is the first frost in Oxbow?
The first hard freeze (28°F) in Oxbow typically arrives around Oct 13, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 29, so the watching starts about Sep 13 — about 170 days after the spring freeze cleared.
How long is the growing season in Oxbow?
Measured between 28°F hard freezes, Oxbow sees about 170 frost-free days — roughly Apr 26 through Oct 13, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 17 to Sep 29, about 135 days.
Is the soil safe to grow vegetables in Oxbow?
The federal record around Oxbow shows 133 documented sites, mostly Nitrate entries (106), the nearest Underground Storage Tanks record about 0.5 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 Oxbow?
From about Sep 13 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 13 (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 13. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Oxbow's scale — its 4a band and its 170-day season. Your yard writes its own version of Oxbow'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 Oxbow’s own scale
6 of the readings below were taken at Oxbow's own scale — its own ~170-day season between 28°F freezes, the 980 acres it covers and 133 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Oxbow's own USDA hardiness band, zones 4aUSDA PHZM 2023
- Oxbow's own 28°F hard-freeze dates, about Apr 26 and Oct 13 and the ~170-day span between themNOAA 1991–2020 Climate Normals
- 133 documented contamination sites on the federal record near Oxbow, the closest Underground Storage Tanks record about 0.5 miles out from the town centreFederal environmental registers
- Oxbow's boundary and the 980 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4a and a ~170-day seasonGrowable Ground crop-matching engine
- The ecoregion at Oxbow's own centroid, the Lake Agassiz PlainUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Oxbow's 980 acres read through its county's SSURGO summaryfrom Cass County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Cass County
- The growing challenges every North Dakota grower plans around — written at state scale, so they stay on the state guidefrom North Dakota
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Cass County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Oxbow's 980 acreswhy one lot differs from the next →
- Which side of Oxbow you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 980 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.5 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 Oxbow-wide figureread your own land →
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