Kiefer, Oklahoma, sits in USDA hardiness zone 7b — a zone band wide enough that plant choice, not possibility, is the interesting question.
Crops well matched to these conditions include cabbage, prickly pear, california poppy, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Even in Kiefer, 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 Kiefer 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 Kiefer — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Kiefer — the short answer
Kiefer, Oklahoma: USDA zone 7b, about 244 days between hard freezes, across 2K acres of town.
- USDA zone
- 7b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 16
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 15
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~244
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 2K 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 7b is Kiefer's average, not your lot's — a low corner or a tree line moves it. Against Kiefer's 244-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Kiefer
Each reading below is measured for Kiefer itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredKiefer runs about 244 days between hard freezes — a long growing season.
There is slack for succession plantings and slow-finishing crops: many vegetables can be sown twice, and the heat-lovers have time to ripen fully.
Plan a second sowing of quick crops after the first comes out, and use the fall window most gardeners let sit idle.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredKiefer sits in USDA hardiness zone 7b.
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 Kiefer is in
Kiefer sits in the Cross Timbers — EPA Level III, inside the wider Great Plains. That is read at Kiefer's own centroid rather than borrowed from Creek County.
What Grows in Kiefer
Every plant below cleared Kiefer's own zone 7b and its 244-day season. Each card opens that plant's Oklahoma profile. How we score.
Is it too late to plant in Kiefer?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Feb 16; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 16 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 15 — long-season crops need about 90 days of runway, quick greens only 30. With a season this long, “too late” mostly means “switch crops” — second sowings and a full fall garden are the norm, with garlic closing the year.
What's on the federal record near Kiefer
Closest first, within ~10 miles of Kiefer. Listing isn't leaking, and distance isn't exposure.
- Kiefer Sub Area OfficeUnderground Storage Tanks · 1200 ft
- Southwestern Bell Telephone CoUnderground Storage Tanks · 1200 ft
- Leon Barnhart Grading & BulldozUnderground Storage Tanks · 1200 ft
- Barnhart ConstructionUnderground Storage Tanks · 1600 ft
- Abandoned Ust Site Vacant LotUnderground Storage Tanks · 2000 ft
- HOWCO KIEFERToxics Release Inventory · 2100 ft
- Kiefer Fast StopUnderground Storage Tanks · 0.6 mi
- Kiefer CornerUnderground Storage Tanks · 0.6 mi
- Kiefer Production OfficeUnderground Storage Tanks · 0.6 mi
- Kiefer Full Service CenterUnderground Storage Tanks · 0.7 mi
- Comet CementersUnderground Storage Tanks · 0.8 mi
- Johnny Carr Grading & BulldozinUnderground Storage Tanks · 0.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Kiefer'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 Kiefer.
Total Sites
453
within ~10 miles of Kiefer
Risk Level
Elevated
Highest-severity
4 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Kiefer
Severity Distribution
within ~10 miles of Kiefer
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Kiefer, two things run higher than the national average within ~10 miles of Kiefer — PFAS (8 sites) and Toxics Release Inventory (54 sites). It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Check your specific parcel in Kiefer
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 Kiefer average
Your land is one point inside Kiefer
Everything above resolves to Kiefer as a whole — one PHZM band and one 28°F frost record, read across 2K 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 Kiefer Average
Kiefer Average
- ●USDA Zones 7b, averaged across Kiefer
- ●One soil character for all of Kiefer
- ●Frost dates read at Kiefer's scale: Mar 16 to Nov 15
YOUR Parcel
- ✓Your exact zone, not Kiefer's 7b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Kiefer
Pull a site-specific report for your exact address in Kiefer, Oklahoma — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Kiefer averages can't show:
We read public map data around Kiefer — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Kiefer average
How we know this about Kiefer
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 Kiefer’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 Kiefer
When does frost risk typically end in Kiefer?
The last hard freeze (28°F) in Kiefer typically lands around Mar 16, 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 Apr 6.
When is the first frost in Kiefer?
The first hard freeze (28°F) in Kiefer typically arrives around Nov 15, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 1, so the watching starts about Oct 16 — about 244 days after the spring freeze cleared.
How long is the growing season in Kiefer?
Measured between 28°F hard freezes, Kiefer sees about 244 frost-free days — roughly Mar 16 through Nov 15, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 6 to Nov 1, about 209 days.
Is the soil safe to grow vegetables in Kiefer?
The federal record around Kiefer is a meaningful one — 453 documented sites, mostly Underground Storage Tanks entries (257), the nearest Underground Storage Tanks 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 Kiefer?
From about Oct 16 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 Nov 15 (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 Nov 15. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Kiefer's scale — its 7b band and its 244-day season. Your yard writes its own version of Kiefer'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 Kiefer’s own scale
6 of the readings below were taken at Kiefer's own scale — its own ~244-day season between 28°F freezes, the 1,523 acres it covers and 453 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Kiefer's own USDA hardiness band, zones 7bUSDA PHZM 2023
- Kiefer's own 28°F hard-freeze dates, about Mar 16 and Nov 15 and the ~244-day span between themNOAA 1991–2020 Climate Normals
- 453 documented contamination sites on the federal record near Kiefer, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Kiefer's boundary and the 1,523 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7b and a ~244-day seasonGrowable Ground crop-matching engine
- The ecoregion at Kiefer's own centroid, the Cross TimbersUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Kiefer's 1,523 acres read through its county's SSURGO summaryfrom Creek County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Creek County
- The growing challenges every Oklahoma grower plans around — written at state scale, so they stay on the state guidefrom Oklahoma
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Creek County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Kiefer's 1,523 acreswhy one lot differs from the next →
- Which side of Kiefer you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,523 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks 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 Kiefer-wide figureread your own land →
More in Oklahoma
Wider growing context
What grows across OklahomaKiefer sits outside our named growing regions, so Oklahoma as a whole is its closest context here.