Fort Defiance, Arizona, sits in USDA hardiness zone 6a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Reliable performers under these conditions include cabbage, blackberry, california poppy, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Fort Defiance, 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 Fort Defiance 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 Fort Defiance — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Fort Defiance — the short answer
Fort Defiance, Arizona: USDA zone 6a, about 150 days between hard freezes, across 4K acres of town.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- May 11
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 8
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~150
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 4K 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 Fort Defiance's average, not your lot's — a low corner or a tree line moves it. Against Fort Defiance's 150-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Fort Defiance
Each reading below is measured for Fort Defiance itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredFort Defiance runs about 150 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
MeasuredFort Defiance 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 Fort Defiance is in
Fort Defiance sits in the Arizona/New Mexico Plateau — EPA Level III, inside the wider North American Deserts. That is read at Fort Defiance's own centroid rather than borrowed from Apache County.
What Grows in Fort Defiance
Every plant below cleared Fort Defiance's own zone 6a and its 150-day season. Each card opens that plant's Arizona profile. How we score.
Is it too late to plant in Fort Defiance?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Apr 13; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near May 11 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 8 — long-season crops need about 90 days of runway, quick greens only 30. As the window narrows, the plantings just get faster — fall brassicas, then greens, then garlic to finish.
What's on the federal record near Fort Defiance
Closest first, within ~10 miles of Fort Defiance. Listing isn't leaking, and distance isn't exposure.
- NAVAJO TRIBAL UTILITY AUTHORITYBrownfields · 1200 ft
- FT DEFIANCE INDIAN HEALTHBrownfields · 1900 ft
- 18 108-03.65X00.85Nitrate · 0.7 mi
- HUGHES MISSILE SYSTEMS CO. NAVAJO FACILITYToxics Release Inventory · 0.7 mi
- BIA BRANCH OF FACILITIES MGMTBrownfields · 0.9 mi
- 18 089-05.40X16.85-1Nitrate · 1.7 mi
- 18 089-05.35X16.61-2Nitrate · 1.7 mi
- 18 089-05.55X16.80Nitrate · 1.9 mi
- NR108.0160X0165Nitrate · 2.6 mi
- 18 089-02.65X14.02Nitrate · 3.5 mi
- NR108.0028X0170Nitrate · 3.8 mi
- 18 108-03.55X04.00Nitrate · 3.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Fort Defiance'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 Fort Defiance.
Total Sites
115
within ~10 miles of Fort Defiance
Risk Level
High
Highest-severity
3 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Fort Defiance
Severity Distribution
within ~10 miles of Fort Defiance
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Fort Defiance, two things run higher than the national average within ~10 miles of Fort Defiance — PFAS (11 sites) and Nitrate (84 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in Fort Defiance
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 Fort Defiance average
Your land is one point inside Fort Defiance
Everything above resolves to Fort Defiance as a whole — one PHZM band and one 28°F frost record, read across 4K 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 Fort Defiance Average
Fort Defiance Average
- ●USDA Zones 6a, averaged across Fort Defiance
- ●One soil character for all of Fort Defiance
- ●Frost dates read at Fort Defiance's scale: May 11 to Oct 8
YOUR Parcel
- ✓Your exact zone, not Fort Defiance's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Fort Defiance
Pull a site-specific report for your exact address in Fort Defiance, Arizona — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Fort Defiance averages can't show:
We read public map data around Fort Defiance — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Fort Defiance average
How we know this about Fort Defiance
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 Fort Defiance’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 Fort Defiance
When does frost risk typically end in Fort Defiance?
The last hard freeze (28°F) in Fort Defiance typically lands around May 11, 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 Jun 1.
When is the first frost in Fort Defiance?
The first hard freeze (28°F) in Fort Defiance typically arrives around Oct 8, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Sep 24, so the watching starts about Sep 8 — about 150 days after the spring freeze cleared.
How long is the growing season in Fort Defiance?
Measured between 28°F hard freezes, Fort Defiance sees about 150 frost-free days — roughly May 11 through Oct 8, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Jun 1 to Sep 24, about 115 days.
Is the soil safe to grow vegetables in Fort Defiance?
The federal record around Fort Defiance runs heavier than most — 115 documented sites, mostly Nitrate entries (84), the nearest Brownfields record about 0.2 miles out — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
How do I protect my plants from frost in Fort Defiance?
From about Sep 8 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 8 (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 8. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Fort Defiance's scale — its 6a band and its 150-day season. Your yard writes its own version of Fort Defiance'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 Fort Defiance’s own scale
6 of the readings below were taken at Fort Defiance's own scale — its own ~150-day season between 28°F freezes, the 4,101 acres it covers and 115 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Fort Defiance's own USDA hardiness band, zones 6aUSDA PHZM 2023
- Fort Defiance's own 28°F hard-freeze dates, about May 11 and Oct 8 and the ~150-day span between themNOAA 1991–2020 Climate Normals
- 115 documented contamination sites on the federal record near Fort Defiance, the closest Brownfields record about 0.2 miles out from the town centreFederal environmental registers
- Fort Defiance's boundary and the 4,101 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~150-day seasonGrowable Ground crop-matching engine
- The ecoregion at Fort Defiance's own centroid, the Arizona/New Mexico PlateauUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Fort Defiance's 4,101 acres read through its county's SSURGO summaryfrom Apache County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Apache County
- The growing challenges every Arizona grower plans around — written at state scale, so they stay on the state guidefrom Arizona
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Apache County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Fort Defiance's 4,101 acreswhy one lot differs from the next →
- Which side of Fort Defiance you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 4,101 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 Fort Defiance-wide figureread your own land →
More in Arizona
Wider growing context
What grows across ArizonaFort Defiance sits outside our named growing regions, so Arizona as a whole is its closest context here.
Nearby growing guides