Grand Forks AFB, North Dakota, sits in USDA hardiness zone 4a — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Expect cabbage, cranberry, turkish rocket, and collard greens to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Even in Grand Forks AFB, 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 Grand Forks AFB 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 Grand Forks AFB — soil, climate, flood, and parcel records. How we handle your address.
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Grand Forks AFB — the short answer
Grand Forks AFB, North Dakota: USDA zone 4a, about 162 days between hard freezes, across 5K acres of town.
- USDA zone
- 4a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 30
- 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
- ~162
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 5K 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 Grand Forks AFB's average, not your lot's — a low corner or a tree line moves it. Against Grand Forks AFB's 162-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Grand Forks AFB
Each reading below is measured for Grand Forks AFB itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredGrand Forks AFB runs about 162 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
MeasuredGrand Forks AFB 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 Grand Forks AFB is in
Grand Forks AFB sits in the Lake Agassiz Plain — EPA Level III, inside the wider Great Plains. That is read at Grand Forks AFB's own centroid rather than borrowed from Grand Forks County.
What Grows in Grand Forks AFB
Every plant below cleared Grand Forks AFB's own zone 4a and its 162-day season. Each card opens that plant's North Dakota profile. How we score.
Is it too late to plant in Grand Forks AFB?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Apr 2; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 30 (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. Even past midsummer there is room for a true fall garden here, and garlic planted near the close carries the momentum into next year.
What's on the federal record near Grand Forks AFB
Closest first, within ~10 miles of Grand Forks AFB. Listing isn't leaking, and distance isn't exposure.
- GENERAL ATOMICS AERONAUTICAL SYSTEMS - GRAND FORKS FLIGHT TEST & TRAINING FACILIBrownfields · 1.6 mi
- NORTHROP GRUMMAN SYSTEMS CORPORATION - EMERADOBrownfields · 1.7 mi
- Baseview Petroleum IncUnderground Storage Tanks · 2.0 mi
- Superpumper 6Underground Storage Tanks · 2.1 mi
- 151-052-06BCCNitrate · 2.4 mi
- 151-053-01CCCNitrate · 2.5 mi
- 151-053-01DCDNitrate · 2.7 mi
- Sand Steel Building Co.Underground Storage Tanks · 2.7 mi
- Emerado SchoolsUnderground Storage Tanks · 2.8 mi
- Nodak Rural Electric Coop IncUnderground Storage Tanks · 2.9 mi
- US AIR FORCE GRAND FORKS AIR FORCE BASE NDToxics Release Inventory · 2.9 mi
- US AIR FORCE GRAND FORKS AIR FORCE BASE NDBrownfields · 2.9 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Grand Forks AFB'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 Grand Forks AFB.
Total Sites
73
within ~10 miles of Grand Forks AFB
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Grand Forks AFB
Severity Distribution
within ~10 miles of Grand Forks AFB
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Grand Forks AFB, Nitrate runs higher than the national average — 52 sites within ~10 miles of Grand Forks AFB. 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 Grand Forks AFB
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 Grand Forks AFB average
Your land is one point inside Grand Forks AFB
Everything above resolves to Grand Forks AFB as a whole — one PHZM band and one 28°F frost record, read across 5K 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 Grand Forks AFB Average
Grand Forks AFB Average
- ●USDA Zones 4a, averaged across Grand Forks AFB
- ●One soil character for all of Grand Forks AFB
- ●Frost dates read at Grand Forks AFB's scale: Apr 30 to Oct 9
YOUR Parcel
- ✓Your exact zone, not Grand Forks AFB's 4a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Grand Forks AFB
Pull a site-specific report for your exact address in Grand Forks AFB, North Dakota — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Grand Forks AFB averages can't show:
We read public map data around Grand Forks AFB — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Grand Forks AFB average
How we know this about Grand Forks AFB
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 Grand Forks AFB’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 Grand Forks AFB
When does frost risk typically end in Grand Forks AFB?
The last hard freeze (28°F) in Grand Forks AFB typically lands around Apr 30, 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 21.
When is the first frost in Grand Forks AFB?
The first hard freeze (28°F) in Grand Forks AFB 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 162 days after the spring freeze cleared.
How long is the growing season in Grand Forks AFB?
Measured between 28°F hard freezes, Grand Forks AFB sees about 162 frost-free days — roughly Apr 30 through Oct 9, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 21 to Sep 25, about 127 days.
Is the soil safe to grow vegetables in Grand Forks AFB?
The federal record around Grand Forks AFB is a meaningful one — 73 documented sites, mostly Nitrate entries (52), the nearest Brownfields record about 1.6 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.
How do I protect my plants from frost in Grand Forks AFB?
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 Grand Forks AFB's scale — its 4a band and its 162-day season. Your yard writes its own version of Grand Forks AFB'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 Grand Forks AFB’s own scale
6 of the readings below were taken at Grand Forks AFB's own scale — its own ~162-day season between 28°F freezes, the 4,800 acres it covers and 73 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Grand Forks AFB's own USDA hardiness band, zones 4aUSDA PHZM 2023
- Grand Forks AFB's own 28°F hard-freeze dates, about Apr 30 and Oct 9 and the ~162-day span between themNOAA 1991–2020 Climate Normals
- 73 documented contamination sites on the federal record near Grand Forks AFB, the closest Brownfields record about 1.6 miles out from the town centreFederal environmental registers
- Grand Forks AFB's boundary and the 4,800 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 4a and a ~162-day seasonGrowable Ground crop-matching engine
- The ecoregion at Grand Forks AFB's own centroid, the Lake Agassiz PlainUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Grand Forks AFB's 4,800 acres read through its county's SSURGO summaryfrom Grand Forks County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Grand Forks 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 Grand Forks County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Grand Forks AFB's 4,800 acreswhy one lot differs from the next →
- Which side of Grand Forks AFB you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 4,800 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields record about 1.6 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 Grand Forks AFB-wide figureread your own land →
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