Centennial, Colorado, sits in USDA hardiness zone 6a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
The conditions favor cabbage, blackberry, california poppy, and collard greens, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in Centennial, 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 Centennial 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 Centennial — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Centennial — the short answer
Centennial, Colorado: USDA zone 6a, about 174 days between hard freezes, across 19K acres of city.
- USDA zone
- 6a
- 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 17
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~174
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 19K 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 6a is Centennial's average, not your lot's — a low corner or a tree line moves it. Against Centennial's 174-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Centennial
Each reading below is measured for Centennial itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredCentennial runs about 174 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
MeasuredCentennial sits in USDA hardiness zone 6a.
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 Centennial is in
Centennial sits in the High Plains — EPA Level III, inside the wider Great Plains. That is read at Centennial's own centroid rather than borrowed from Arapahoe County.
What Grows in Centennial
Every plant below cleared Centennial's own zone 6a and its 174-day season. Each card opens that plant's Colorado profile. How we score.
Is it too late to plant in Centennial?
Too late for some crops, right on time for others — a growing season is a sequence, not a deadline. 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 17 — 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 Centennial
Closest first, within ~10 miles of Centennial. Listing isn't leaking, and distance isn't exposure.
- POWERSECURE - WALMART # 3313Brownfields · 1000 ft
- Circle K Store #2709845Underground Storage Tanks · 1100 ft
- HOLMAN HONDABrownfields · 1200 ft
- Murphy Express #8769Underground Storage Tanks · 1400 ft
- Centura HealthUnderground Storage Tanks · 1600 ft
- FEDEX APAABrownfields · 1800 ft
- Horner ConstructionUnderground Storage Tanks · 1900 ft
- AUTONATION MAZDA ARAPAHOEBrownfields · 2100 ft
- My Goods Market #6495Underground Storage Tanks · 2200 ft
- CLOCK SPRING / NRIBrownfields · 2200 ft
- Vacant Lot Nw CornerUnderground Storage Tanks · 2200 ft
- HOME DEPOT STORE #1509Brownfields · 2200 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Centennial'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 Centennial.
Sources Checked
within ~10 miles of Centennial
Severity Distribution
within ~10 miles of Centennial
Highest-Severity Sites
Know Before You Grow
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
- •Near a brownfield, raised beds of imported soil give your food clean ground.
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
Check your specific parcel in Centennial
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 Centennial average
Your land is one point inside Centennial
Everything above resolves to Centennial as a whole — one PHZM band and one 28°F frost record, read across 19K 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 Centennial Average
Centennial Average
- ●USDA Zones 6a, averaged across Centennial
- ●One soil character for all of Centennial
- ●Frost dates read at Centennial's scale: Apr 26 to Oct 17
YOUR Parcel
- ✓Your exact zone, not Centennial's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Centennial
Pull a site-specific report for your exact address in Centennial, Colorado — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Centennial averages can't show:
We read public map data around Centennial — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Centennial average
How we know this about Centennial
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 Centennial’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 Centennial
When does frost risk typically end in Centennial?
The last hard freeze (28°F) in Centennial 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 Centennial?
The first hard freeze (28°F) in Centennial typically arrives around Oct 17, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 3, so the watching starts about Sep 17 — about 174 days after the spring freeze cleared.
How long is the growing season in Centennial?
Measured between 28°F hard freezes, Centennial sees about 174 frost-free days — roughly Apr 26 through Oct 17, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 17 to Oct 3, about 139 days.
Is the soil safe to grow vegetables in Centennial?
The federal record around Centennial is a meaningful one — 2,443 documented sites, mostly Underground Storage Tanks entries (1,189), 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 Centennial?
From about Sep 17 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 17 (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 17. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Centennial's scale — its 6a band and its 174-day season. Your yard writes its own version of Centennial'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 Centennial’s own scale
6 of the readings below were taken at Centennial's own scale — its own ~174-day season between 28°F freezes, the 19,300 acres it covers and 2,443 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Centennial's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Centennial's own 28°F hard-freeze dates, about Apr 26 and Oct 17 and the ~174-day span between themNOAA 1991–2020 Climate Normals
- 2,443 documented contamination sites on the federal record near Centennial, the closest Brownfields record about 0.2 miles out from the town centreFederal environmental registers
- Centennial's boundary and the 19,300 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~174-day seasonGrowable Ground crop-matching engine
- The ecoregion at Centennial's own centroid, the High PlainsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Centennial's 19,300 acres read through its county's SSURGO summaryfrom Arapahoe County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Arapahoe 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 Arapahoe County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Centennial's 19,300 acreswhy one lot differs from the next →
- Which side of Centennial you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 19,300 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 Centennial-wide figureread your own land →