Nunn, Colorado, sits in USDA hardiness zone 5b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
On paper, cabbage, cranberry, lavender, and collard greens all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in Nunn, 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 Nunn 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 Nunn — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Nunn — the short answer
Nunn, Colorado: USDA zone 5b, about 162 days between hard freezes, across 3K acres of town.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 1
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 10
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~162
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 3K 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 5b is Nunn's average, not your lot's — a low corner or a tree line moves it. Against Nunn's 162-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Nunn
Each reading below is measured for Nunn itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredNunn 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
MeasuredNunn sits in USDA hardiness zone 5b.
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 Nunn is in
Nunn sits in the High Plains — EPA Level III, inside the wider Great Plains. That is read at Nunn's own centroid rather than borrowed from Weld County.
What Grows in Nunn
Every plant below cleared Nunn's own zone 5b and its 162-day season. Each card opens that plant's Colorado profile. How we score.
Is it too late to plant in Nunn?
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 3; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 1 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 10 — 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.
What's on the federal record near Nunn
Closest first, within ~10 miles of Nunn. Listing isn't leaking, and distance isn't exposure.
- EXTERRANBrownfields · 1100 ft
- GRAYMAR ENVIRONMENTAL SERVICES LLCBrownfields · 2100 ft
- Weld County School - NunnUnderground Storage Tanks · 0.6 mi
- Ee Foster Estate PropertyUnderground Storage Tanks · 0.8 mi
- Cerro Summit Rr 250609Underground Storage Tanks · 0.8 mi
- FE WARREN #11 DOD FUDS SITEBrownfields · 0.9 mi
- SB00906633CAC USGS 404203104470801Nitrate · 0.9 mi
- SB00906633CAC USGS 404202104470201Nitrate · 0.9 mi
- CDOT NunnUnderground Storage Tanks · 0.9 mi
- Weld County Road & Bridge NunnUnderground Storage Tanks · 1.0 mi
- K Eugene AyersUnderground Storage Tanks · 1.2 mi
- SB00806622AABNitrate · 4.4 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Nunn'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 Nunn.
Total Sites
65
within ~10 miles of Nunn
Risk Level
Elevated
Highest-severity
1 Superfund site (none NPL-listed)
Sources Checked
within ~10 miles of Nunn
Severity Distribution
within ~10 miles of Nunn
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Nunn, Nitrate runs higher than the national average — 32 sites within ~10 miles of Nunn. 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 Nunn
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 Nunn average
Your land is one point inside Nunn
Everything above resolves to Nunn as a whole — one PHZM band and one 28°F frost record, read across 3K 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 Nunn Average
Nunn Average
- ●USDA Zones 5b, averaged across Nunn
- ●One soil character for all of Nunn
- ●Frost dates read at Nunn's scale: May 1 to Oct 10
YOUR Parcel
- ✓Your exact zone, not Nunn's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Nunn
Pull a site-specific report for your exact address in Nunn, Colorado — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Nunn averages can't show:
We read public map data around Nunn — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Nunn average
How we know this about Nunn
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 Nunn’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 Nunn
When does frost risk typically end in Nunn?
The last hard freeze (28°F) in Nunn typically lands around May 1, 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 22.
When is the first frost in Nunn?
The first hard freeze (28°F) in Nunn typically arrives around Oct 10, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 26, so the watching starts about Sep 10 — about 162 days after the spring freeze cleared.
How long is the growing season in Nunn?
Measured between 28°F hard freezes, Nunn sees about 162 frost-free days — roughly May 1 through Oct 10, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 22 to Sep 26, about 127 days.
Is the soil safe to grow vegetables in Nunn?
The federal record around Nunn is a meaningful one — 65 documented sites, mostly Nitrate entries (32), the nearest Brownfields record about 0.2 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 Nunn?
From about Sep 10 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 10 (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 10. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Nunn's scale — its 5b band and its 162-day season. Your yard writes its own version of Nunn'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 Nunn’s own scale
6 of the readings below were taken at Nunn's own scale — its own ~162-day season between 28°F freezes, the 2,547 acres it covers and 65 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Nunn's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Nunn's own 28°F hard-freeze dates, about May 1 and Oct 10 and the ~162-day span between themNOAA 1991–2020 Climate Normals
- 65 documented contamination sites on the federal record near Nunn, the closest Brownfields record about 0.2 miles out from the town centreFederal environmental registers
- Nunn's boundary and the 2,547 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~162-day seasonGrowable Ground crop-matching engine
- The ecoregion at Nunn's own centroid, the High PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Nunn's 2,547 acres read through its county's SSURGO summaryfrom Weld County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Weld County
- The growing challenges every Colorado grower plans around — written at state scale, so they stay on the state guidefrom Colorado
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Weld County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Nunn's 2,547 acreswhy one lot differs from the next →
- Which side of Nunn you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,547 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields 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 Nunn-wide figureread your own land →
More in Colorado
Growing regions
Nearby growing guides