Hamblen County, in Tennessee, sits in USDA hardiness zone 7b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
On paper, cabbage, prickly pear, california poppy, and collard greens all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Hamblen County lies within Appalachia — a regional growing area with its own character.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
Hamblen County holds more than one microclimate.
Soils and elevations shift across Hamblen 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 Hamblen County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Hamblen County — the short answer
Hamblen County, Tennessee: USDA zone 7b, about 231 days between hard freezes, across 103K acres.
- USDA zone
- 7b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 25
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Nov 11
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~231
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 103K 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 7b is Hamblen County's average, not your lot's — a low corner or a tree line moves it. Against Hamblen County's 231-day season, see what your own ground reads.
Heat and winter chill in Hamblen County
Across a year, Hamblen County accumulates about 3,782 growing degree days above 50°F, about 331 fewer than the middle Tennessee county — ahead of 18 of Tennessee’s 95 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 2,178 hours below 45°F, 119 more than the Tennessee middle of 2,059. 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 Hamblen County
Across Hamblen County, the ground is predominantly Ultisols, where Dewey, Dandridge, and Talbott are the most extensive named soil series. The soil is generally well drained with a silt loam surface. Topsoil pH runs about 5.0–5.6, strongly acidic. Rainfall drains through hydrologic group B soils.
Soil order
Ultisols
Drainage
Well drained
Prime farmland
8%
Hydric soils
0%
Soil still varies lot by lot — soil types explained.
How the ground varies across Hamblen County
The USDA soil survey maps 68% of Hamblen County as well drained — but another 18% drains differently: 11% excessively drained, 5% moderately well drained.
Dewey is the most extensive named soil at 23% of mapped acres, then Dandridge (14%) and Talbott (12%).
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 Hamblen County
Each reading below is measured for Hamblen 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 Hamblen 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 Hamblen County runs about pH 5.0–5.6, 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
MeasuredHamblen County runs about 231 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
MeasuredHamblen County 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 Hamblen County is in
Hamblen County sits in the Ridge and Valley — EPA Level III, inside the wider Eastern Temperate Forests. One consistent ecological setting across the whole county.
What Grows in Hamblen County
We scored all 1,086 plants against Hamblen County's own USDA zone 7b and its own 231-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 Tennessee profile.
Is it too late to plant in Hamblen County?
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 Feb 25; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 25 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 11 — 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.
Documented around Hamblen County
Survey cells within 31 miles of Hamblen County checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 58 miles off. What to watch for.
What gets applied to farmland in Hamblen County
USGS estimates 17,555 lb of Glyphosate on Hamblen County farmland in 2019, its largest by weight, ahead of Atrazine (5,753 lb) and 2,4-d (3,109 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 Hamblen County — and how to grow with it.
We checked the federal record across Hamblen County — 361 documented sites across 6 of the 9 source types we track.
The most significant on record: 5 Superfund sites (none NPL-listed). Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
There's a meaningful federal record across Hamblen County — worth a look before you plant food, not a reason to hold back from growing. Proximity to a documented site is information, not a diagnosis of any one yard. A soil test before new food beds is the sensible precaution here, and the map shows exactly which sites sit where, so you can see what's actually near you.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Hamblen County
Closest first, across Hamblen County. Listing isn't leaking, and distance isn't exposure.
- By-Lo Market #34Underground Storage Tanks · 850 ft
- Flav-o-rich IncUnderground Storage Tanks · 1300 ft
- College Square MarketUnderground Storage Tanks · 1600 ft
- Morristown MartUnderground Storage Tanks · 1900 ft
- Murphy USA #6710Underground Storage Tanks · 0.5 mi
- WALMART SUPERCENTER #685Brownfields · 0.5 mi
- Berkline Corp Plant No. 318Underground Storage Tanks · 0.5 mi
- Suburban ShellUnderground Storage Tanks · 0.5 mi
- Affordable Tire ServiceUnderground Storage Tanks · 0.6 mi
- Fastop Food Mart #5Underground Storage Tanks · 0.6 mi
- Coco Cola Distribution FacilityUnderground Storage Tanks · 0.6 mi
- BERKLINE, LLC PLANT #1Toxics Release Inventory · 0.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Hamblen 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 Hamblen County.
Total Sites
361
across Hamblen County
Risk Level
Elevated
Highest-severity
5 Superfund sites (none NPL-listed)
Sources Checked
across Hamblen County
Severity Distribution
across Hamblen County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Hamblen County, two things run higher than the national average across Hamblen County — Toxics Release Inventory (54 sites) and Underground Storage Tanks (252 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
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 Hamblen 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 Hamblen County average
Your land is one point inside Hamblen County
Everything above resolves to Hamblen County as a whole — one PHZM band and one county frost record, read across 103K 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 Hamblen County Average
Hamblen County Average
- ●USDA Zones 7b, averaged across Hamblen County
- ●One soil character for all of Hamblen County
- ●Frost dates read at Hamblen County's scale: Mar 25 to Nov 11
YOUR Parcel
- ✓Your exact zone, not Hamblen County's 7b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Hamblen County
Pull a site-specific report for your exact address in Hamblen County, Tennessee — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Hamblen County averages can't show:
We read public map data around Hamblen County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Hamblen County average
How we know this about Hamblen 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 Hamblen County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Hamblen County
When does frost risk typically end in Hamblen County?
The last hard freeze (28°F) in Hamblen County typically lands around Mar 25, 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 15.
How long is the growing season in Hamblen County?
Measured between 28°F hard freezes, Hamblen County sees about 231 frost-free days — roughly Mar 25 through Nov 11, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 15 to Oct 28, about 196 days.
Is the soil safe to grow vegetables in Hamblen County?
The federal record around Hamblen County is a meaningful one — 361 documented sites, mostly Underground Storage Tanks entries (252), 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.
Everything above is measured at Hamblen County's scale — its 7b band and its 231-day season. Your yard writes its own version of Hamblen 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 Tennessee's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Hamblen County’s own scale
8 of the readings below were taken at Hamblen County's own scale — its own ~231-day span between 28°F freezes, the 3 most extensive soil series mapped here and 361 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Hamblen County's own USDA hardiness band, zones 7bUSDA PHZM 2023
- Hamblen County's own 28°F hard-freeze dates and its ~231-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Hamblen CountyUSDA NRCS SSURGO
- 361 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Underground Storage Tanks record about 0.2 miles outFederal environmental registers
- Hamblen County's boundary and the 103,161 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7b and a ~231-day seasonGrowable Ground crop-matching engine
- Hamblen County sitting wholly inside the Ridge and ValleyUS EPA Level III Ecoregions
- Which agricultural compounds go onto Hamblen County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Tennessee grower plans around — written at state scale, so they stay on the state guidefrom Tennessee
What this page can’t tell you
- How the season shifts across Hamblen County — the ~231 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 Hamblen County's 103,161 acreswhy one lot differs from the next →
- Which of those 361 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 Hamblen Countyread your own land →