Polk County, in North Carolina, sits in USDA hardiness zone 8a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Crops well matched to these conditions include cabbage, fig, california poppy, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Polk County lies within the Piedmont — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Polk County holds more than one microclimate.
Soils and elevations shift across Polk County, so your frost dates and drainage aren't the county average. 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 Polk County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Polk County — the short answer
Polk County, North Carolina: USDA zone 8a, about 243 days between hard freezes, across 152K acres.
- USDA zone
- 8a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 17
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Nov 15
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~243
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 152K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are county 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 Polk County's average, not your lot's — a low corner or a tree line moves it. Against Polk County's 243-day season, see what your own ground reads.
Heat and winter chill in Polk County
Across a year, Polk County accumulates about 4,156 growing degree days above 50°F, about 234 fewer than the middle North Carolina county — ahead of 33 of North Carolina’s 100 counties. Degree days are the heat a crop actually gets to work with — more of them is more room to ripen a long-season crop before the freeze closes the window.
Winter banks about 1,778 hours below 45°F, 15 more than the North Carolina middle of 1,763. Chill is what tells a fruit tree its dormancy is over, and it is set by climate rather than by anything you can build.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Polk County
Across Polk County, the ground is predominantly Ultisols, where Pacolet, Madison, and Rion are the most extensive named soil series. The soil is generally well drained with a sandy clay loam surface. Topsoil pH runs about 5.3–5.5, strongly acidic. Rainfall drains through hydrologic group B soils.
Soil order
Ultisols
Drainage
Well drained
Prime farmland
14%
Hydric soils
1%
Soil still varies lot by lot — soil types explained.
How the ground varies across Polk County
The USDA soil survey maps 91% of Polk County as well drained — but another 8% drains differently: 3% moderately well drained, 2% somewhat excessively drained.
Pacolet is the most extensive named soil at 22% of mapped acres, then Madison (11%) and Rion (9%).
Which of them your own lot sits on is a parcel question, not a county one. Check your address for the survey at your boundary.
What this means for growing in Polk County
Each reading below is measured for Polk County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Polk County are well drained, in hydrologic group B — ground that drains quickly.
The upside is soil you can work early in spring and roots that never drown; the cost is that fast-draining ground dries out fast and leaches nutrients away before plants can use them.
Work in compost and mulch to hold moisture and feed, and water more often in short doses than deep and rarely.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Polk County runs about pH 5.3–5.5, on the acidic side.
Blueberries, potatoes, and rhododendrons thrive in it, but most vegetables start locking out nutrients below about pH 6.0 and grow pale and stunted no matter how much you feed them.
A measured lime application raises pH for the crops that need it — but test first, because the right rate depends on your own soil, not the county average.
USDA NRCS SSURGO
Season length
MeasuredPolk County runs about 243 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
MeasuredPolk County 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 Polk County is in
Polk County spans 2 EPA Level III ecoregions — Piedmont (73%) and Blue Ridge (27%). Which one your land falls in changes what grows wild there and how the ground behaves, and a county-wide answer cannot tell you which.
What Grows in Polk County
We scored all 1,086 plants against Polk County's own USDA zone 8a and its own 243-day season between hard freezes, using the same matching engine that runs a full parcel report. These cleared both. Sun, soil pH and drainage vary lot by lot — those are the parcel questions below. Each card opens that plant's North Carolina profile.
Is it too late to plant in Polk County?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 17; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 17 (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. Here the season winds down slowly: late sowings, a real autumn harvest, and garlic in the ground before the first hard freeze.
Documented around Polk County
Survey cells within 31 miles of Polk County checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 32 miles off. What to watch for.
What gets applied to farmland in Polk County
USGS estimates 2,315 lb of 2,4-d on Polk County farmland in 2019, its largest by weight, ahead of Glyphosate (2,183 lb) and Dicamba (606 lb).
Farmland across the whole county, not any one lot. Check your address for the site-by-site record.
Safe to Grow Here?
What the federal record shows across Polk County — and how to grow with it.
We checked the federal record across Polk County — 73 documented sites across 4 of the 9 source types we track.
The most significant on record: 4 Toxics Release Inventory facilities. Active industrial facilities reporting chemical releases to air, water, and land.
The federal record across Polk County is a modest one — a typical footprint for a growing area. Nothing here calls for alarm; it's worth knowing which recorded sites sit closest to where you grow, and each one on the map carries its type and location. If one turns out to be a near neighbor, a one-time soil test settles the question.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Polk County
Closest first, across Polk County. Listing isn't leaking, and distance isn't exposure.
- MIDWAY SERVICE STATIONUnderground Storage Tanks · 0.7 mi
- WOODLAND MILLS CORPORATIONBrownfields · 1.2 mi
- TIMKENSTEEL CORP - TRYON PEAKBrownfields · 1.2 mi
- TIMKENSTEEL CORP - TRYON PEAKToxics Release Inventory · 1.2 mi
- ROADRUNNER MARKET 6058Underground Storage Tanks · 1.3 mi
- LEROY WALDROP'S GROCERYUnderground Storage Tanks · 1.4 mi
- DEBS MINI MART 4Underground Storage Tanks · 1.4 mi
- DEBS MINI MARTUnderground Storage Tanks · 1.4 mi
- YOUNGBLOOD OIL COBrownfields · 1.9 mi
- COLUMBUS REMOTE OFFICEUnderground Storage Tanks · 1.9 mi
- MILLIKEN & COMPANY - HATCH PLANTBrownfields · 1.9 mi
- MILLIKEN & COMPANY - HATCH PLANTToxics Release Inventory · 1.9 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Polk County'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 Polk County.
Total Sites
73
across Polk County
Risk Level
Moderate
Highest-severity
4 Toxics Release Inventory facilities
Sources Checked
across Polk County
Severity Distribution
across Polk County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Polk County, Underground Storage Tanks runs higher than the national average — 52 sites across Polk County. That's not a problem with your land — it's information about it.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Polk County
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 Polk County average
Your land is one point inside Polk County
Everything above resolves to Polk County as a whole — one PHZM band and one county frost record, read across 152K 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 county 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 county average.
Your Lot vs the Polk County Average
Polk County Average
- ●USDA Zones 8a, averaged across Polk County
- ●One soil character for all of Polk County
- ●Frost dates read at Polk County's scale: Mar 17 to Nov 15
YOUR Parcel
- ✓Your exact zone, not Polk County's 8a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Polk County
Pull a site-specific report for your exact address in Polk County, North Carolina — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Polk County averages can't show:
We read public map data around Polk County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Polk County average
How we know this about Polk County
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at county grain; hard-freeze dates from NOAA 1991–2020 28°F normals at this county’s own record where one resolves, and the labelled statewide window where none does; soils from the USDA NRCS SSURGO survey, area-weighted across the county’s own map units; boundaries and acreage from US Census TIGER/Line 2025; the contamination and pesticide records from the federal sources named in their beats above. Where Polk County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Polk County
When does frost risk typically end in Polk County?
The last hard freeze (28°F) in Polk County typically lands around Mar 17, 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 7.
How long is the growing season in Polk County?
Measured between 28°F hard freezes, Polk County sees about 243 frost-free days — roughly Mar 17 through Nov 15, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 7 to Nov 1, about 208 days.
Is the soil safe to grow vegetables in Polk County?
The federal record around Polk County shows 73 documented sites, mostly Underground Storage Tanks entries (52), 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.
Everything above is measured at Polk County's scale — its 8a band and its 243-day season. Your yard writes its own version of Polk County's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads North Carolina's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Polk County’s own scale
8 of the readings below were taken at Polk County's own scale — its own ~243-day span between 28°F freezes, the 3 most extensive soil series mapped here and 73 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Polk County's own USDA hardiness band, zones 8aUSDA PHZM 2023
- Polk County's own 28°F hard-freeze dates and its ~243-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Polk CountyUSDA NRCS SSURGO
- 73 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Underground Storage Tanks record about 0.7 miles outFederal environmental registers
- Polk County's boundary and the 152,120 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 8a and a ~243-day seasonGrowable Ground crop-matching engine
- The 2 ecoregions Polk County spans, Piedmont the largestUS EPA Level III Ecoregions
- Which agricultural compounds go onto Polk County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every North Carolina grower plans around — written at state scale, so they stay on the state guidefrom North Carolina
What this page can’t tell you
- How the season shifts across Polk County — the ~243 days above is one reading at its centre; the 12 towns below each carry their owntowns in this county →
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Polk County's 152,120 acreswhy one lot differs from the next →
- Which of those 73 documented sites actually reaches your soil — that needs your address, the wind, and the groundwater directionhow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — none of it survives being averaged over Polk Countyread your own land →