Smyth County, in Virginia, sits in USDA hardiness zone 7a — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
On paper, cabbage, pawpaw, california poppy, and collard greens all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Smyth 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
Smyth County holds more than one microclimate.
Soils and elevations shift across Smyth 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 Smyth County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Smyth County — the short answer
Smyth County, Virginia: USDA zone 7a, about 192 days between hard freezes, across 289K acres.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 13
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Oct 22
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~192
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 289K 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 7a is Smyth County's average, not your lot's — a low corner or a tree line moves it. Against Smyth County's 192-day season, see what your own ground reads.
Heat in Smyth County
Across a year, Smyth County accumulates about 2,871 growing degree days above 50°F, about 863 fewer than the middle Virginia county — ahead of 10 of Virginia’s 133 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.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Smyth County
Across Smyth County, the ground is predominantly Ultisols, where Frederick, Carbo, and Lily are the most extensive named soil series. The soil is generally well drained with a silt loam surface. Topsoil pH runs about 4.8–6.0, strongly acidic. Rainfall drains through hydrologic group B soils.
Soil order
Ultisols
Drainage
Well drained
Prime farmland
6%
Hydric soils
1%
Soil still varies lot by lot — soil types explained.
How the ground varies across Smyth County
The USDA soil survey maps 91% of Smyth County as well drained — but another 8% drains differently: 5% somewhat excessively drained, 1% moderately well drained.
Frederick is the most extensive named soil at 22% of mapped acres, then Carbo (10%) and Lily (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 Smyth County
Each reading below is measured for Smyth 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 Smyth 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 Smyth County runs about pH 4.8–6.0, 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
MeasuredSmyth County runs about 192 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
MeasuredSmyth County sits in USDA hardiness zone 7a.
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 Smyth County is in
Smyth County spans 2 EPA Level III ecoregions — Ridge and Valley (72%) and Blue Ridge (28%). 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 Smyth County
We scored all 1,086 plants against Smyth County's own USDA zone 7a and its own 192-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 Virginia profile.
Is it too late to plant in Smyth 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 Mar 16; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 13 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 22 — long-season crops need about 90 days of runway, quick greens only 30. Late in the year the fall bench takes over — quick greens, radishes, and garlic that repays you next summer.
Documented around Smyth County
Spotted lanternfly documented 27 miles from Smyth County, first recorded 2021. What to watch for.
- Japanese beetle10 documented records
- monarch butterfly3 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Smyth County
USGS estimates 10,441 lb of Glyphosate on Smyth County farmland in 2019, its largest by weight, ahead of Atrazine (6,679 lb) and Metolachlor & Metolachlor-s (6,123 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 Smyth County — and how to grow with it.
We checked the federal record across Smyth County — 313 documented sites across 7 of the 9 source types we track.
The most significant on record: 1 Superfund site. 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 Smyth 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 Smyth County
Closest first, across Smyth County. Listing isn't leaking, and distance isn't exposure.
- HOLSTON HILLS COUNTRY CLUB, INCUnderground Storage Tanks · 1.0 mi
- Minit Mart 2Underground Storage Tanks · 1.0 mi
- FREDS MARKETUnderground Storage Tanks · 1.0 mi
- NELLIE WILSON STOREUnderground Storage Tanks · 1.0 mi
- SOYERS SAND COUnderground Storage Tanks · 1.1 mi
- CHARLES S. GLENNUnderground Storage Tanks · 1.1 mi
- Smile Stations LLCUnderground Storage Tanks · 1.1 mi
- Valley Grocery and Laurel Valley CafeUnderground Storage Tanks · 1.1 mi
- BRUCE V. BLEVINS GAS STATIONUnderground Storage Tanks · 1.1 mi
- AMERICAN BAKERIES INCUnderground Storage Tanks · 1.1 mi
- WEST END TEXACOUnderground Storage Tanks · 1.2 mi
- Marion MarathonUnderground Storage Tanks · 1.2 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Smyth 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 Smyth County.
Sources Checked
across Smyth County
Severity Distribution
across Smyth County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Smyth County, two things run higher than the national average across Smyth County — Mining (36 sites) and PFAS (3 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Mining: Mining sites — both historic and active — can leach heavy metals (arsenic, lead, cadmium, mercury) into soil and water for centuries after operations cease.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Test soil for heavy metals (lead, arsenic, cadmium, mercury) — this is essential near any mining site.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check your specific parcel in Smyth 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 Smyth County average
Your land is one point inside Smyth County
Everything above resolves to Smyth County as a whole — one PHZM band and one county frost record, read across 289K 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 Smyth County Average
Smyth County Average
- ●USDA Zones 7a, averaged across Smyth County
- ●One soil character for all of Smyth County
- ●Frost dates read at Smyth County's scale: Apr 13 to Oct 22
YOUR Parcel
- ✓Your exact zone, not Smyth County's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Smyth County
Pull a site-specific report for your exact address in Smyth County, Virginia — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Smyth County averages can't show:
We read public map data around Smyth County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Smyth County average
How we know this about Smyth 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 Smyth County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Smyth County
When does frost risk typically end in Smyth County?
The last hard freeze (28°F) in Smyth County typically lands around Apr 13, 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 May 4.
How long is the growing season in Smyth County?
Measured between 28°F hard freezes, Smyth County sees about 192 frost-free days — roughly Apr 13 through Oct 22, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 4 to Oct 8, about 157 days.
Is the soil safe to grow vegetables in Smyth County?
The federal record around Smyth County is a meaningful one — 313 documented sites, mostly Underground Storage Tanks entries (186), the nearest Underground Storage Tanks record about 1.0 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 Smyth County's scale — its 7a band and its 192-day season. Your yard writes its own version of Smyth 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 Virginia's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Smyth County’s own scale
9 of the readings below were taken at Smyth County's own scale — its own ~192-day span between 28°F freezes, the 3 most extensive soil series mapped here and 313 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Smyth County's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Smyth County's own 28°F hard-freeze dates and its ~192-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Smyth CountyUSDA NRCS SSURGO
- 313 documented contamination sites inside the county boundary, distance-sorted from its center — the closest Underground Storage Tanks record about 1.0 miles outFederal environmental registers
- Smyth County's boundary and the 288,921 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~192-day seasonGrowable Ground crop-matching engine
- The 2 ecoregions Smyth County spans, Ridge and Valley the largestUS EPA Level III Ecoregions
- Open occurrence records documented in Smyth County for 2 tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Smyth County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Virginia grower plans around — written at state scale, so they stay on the state guidefrom Virginia
What this page can’t tell you
- How the season shifts across Smyth County — the ~192 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 Smyth County's 288,921 acreswhy one lot differs from the next →
- Which of those 313 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 Smyth Countyread your own land →