Hennepin, Oklahoma, sits in USDA hardiness zone 8a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
These conditions suit cabbage, fig, california poppy, and collard greens — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
Even in Hennepin, 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 Hennepin 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 Hennepin — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Hennepin — the short answer
Hennepin, Oklahoma: USDA zone 8a, about 249 days between hard freezes, across 1K acres of town.
- USDA zone
- 8a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 14
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 18
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~249
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 1K 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 8a is Hennepin's average, not your lot's — a low corner or a tree line moves it. Against Hennepin's 249-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Hennepin
Each reading below is measured for Hennepin itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredHennepin runs about 249 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
MeasuredHennepin sits in USDA hardiness zone 8a.
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 Hennepin is in
Hennepin sits in the Cross Timbers — EPA Level III, inside the wider Great Plains. That is read at Hennepin's own centroid, and it is not what its county reads: Garvin County is mostly Central Great Plains. The wider page above you is answering a different question about different ground.
What Grows in Hennepin
Every plant below cleared Hennepin's own zone 8a and its 249-day season. Each card opens that plant's Oklahoma profile. How we score.
Is it too late to plant in Hennepin?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Feb 14; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 14 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 18 — long-season crops need about 90 days of runway, quick greens only 30. There is slack in a calendar like this — late plantings, second rounds of favorites, and a fall bench that keeps beds working.
What's on the federal record near Hennepin
Closest first, within ~10 miles of Hennepin. Listing isn't leaking, and distance isn't exposure.
- Johnson PropertyUnderground Storage Tanks · 0.7 mi
- Okla Dept Of TransportationUnderground Storage Tanks · 1.5 mi
- Ellen Steven's HouseUnderground Storage Tanks · 2.9 mi
- Tex/Com Energy Co.Underground Storage Tanks · 5.4 mi
- Breaths ExxonUnderground Storage Tanks · 7.0 mi
- Former Yarnell Grocery & Meat MarketUnderground Storage Tanks · 7.1 mi
- Tatums Service StationUnderground Storage Tanks · 7.2 mi
- Wingo GroceryUnderground Storage Tanks · 7.2 mi
- TEST FACILITY-OPS DEMO1Toxics Release Inventory · 7.3 mi
- HOWARD ENERGY PARTNERS / TATUMS COMPRESSOR STATIONBrownfields · 7.4 mi
- Thrift #61422 (100229)Underground Storage Tanks · 7.7 mi
- Former Service StationUnderground Storage Tanks · 7.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Hennepin'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 Hennepin.
Total Sites
43
within ~10 miles of Hennepin
Risk Level
Moderate
Highest-severity
4 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Hennepin
Severity Distribution
within ~10 miles of Hennepin
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Hennepin, two things run higher than the national average within ~10 miles of Hennepin — Toxics Release Inventory (4 sites) and Underground Storage Tanks (28 sites). That's not a problem with your land — it's information about it.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Hennepin
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 Hennepin average
Your land is one point inside Hennepin
Everything above resolves to Hennepin as a whole — one PHZM band and one 28°F frost record, read across 1K 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 Hennepin Average
Hennepin Average
- ●USDA Zones 8a, averaged across Hennepin
- ●One soil character for all of Hennepin
- ●Frost dates read at Hennepin's scale: Mar 14 to Nov 18
YOUR Parcel
- ✓Your exact zone, not Hennepin's 8a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Hennepin
Pull a site-specific report for your exact address in Hennepin, Oklahoma — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Hennepin averages can't show:
We read public map data around Hennepin — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Hennepin average
How we know this about Hennepin
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 Hennepin’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 Hennepin
When does frost risk typically end in Hennepin?
The last hard freeze (28°F) in Hennepin typically lands around Mar 14, 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 4.
When is the first frost in Hennepin?
The first hard freeze (28°F) in Hennepin typically arrives around Nov 18, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 4, so the watching starts about Oct 19 — about 249 days after the spring freeze cleared.
How long is the growing season in Hennepin?
Measured between 28°F hard freezes, Hennepin sees about 249 frost-free days — roughly Mar 14 through Nov 18, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 4 to Nov 4, about 214 days.
Is the soil safe to grow vegetables in Hennepin?
The federal record around Hennepin shows 43 documented sites, mostly Underground Storage Tanks entries (28), the nearest Underground Storage Tanks record about 0.7 miles out — a typical footprint for a growing area, and proximity to a documented site is information, not a diagnosis of any one yard. It's worth seeing which recorded sites sit closest to where you grow, and testing the soil before new food beds near any of them.
How do I protect my plants from frost in Hennepin?
From about Oct 19 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 18 (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 18. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Hennepin's scale — its 8a band and its 249-day season. Your yard writes its own version of Hennepin'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 Hennepin’s own scale
6 of the readings below were taken at Hennepin's own scale — its own ~249-day season between 28°F freezes, the 1,021 acres it covers and 43 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Hennepin's own USDA hardiness band, zones 8aUSDA PHZM 2023
- Hennepin's own 28°F hard-freeze dates, about Mar 14 and Nov 18 and the ~249-day span between themNOAA 1991–2020 Climate Normals
- 43 documented contamination sites on the federal record near Hennepin, the closest Underground Storage Tanks record about 0.7 miles out from the town centreFederal environmental registers
- Hennepin's boundary and the 1,021 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8a and a ~249-day seasonGrowable Ground crop-matching engine
- Hennepin sits in the Cross Timbers — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
Inherited from a wider read
- Soil character — no town-scale survey exists, so Hennepin's 1,021 acres read through its county's SSURGO summaryfrom Garvin County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Garvin 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 Garvin County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Hennepin's 1,021 acreswhy one lot differs from the next →
- Which side of Hennepin you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,021 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.7 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 Hennepin-wide figureread your own land →
More in Oklahoma
Wider growing context
What grows across OklahomaHennepin sits outside our named growing regions, so Oklahoma as a whole is its closest context here.
Nearby growing guides