Opal, Virginia, sits in USDA hardiness zone 7a — a zone band wide enough that plant choice, not possibility, is the interesting question.
Crops well matched to these conditions include cabbage, hazelnut, california poppy, and collard greens — though what thrives on any one site still turns on its specific soil, sun, and drainage.
Even in Opal, 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 Opal 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 Opal — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Opal — the short answer
Opal, Virginia: USDA zone 7a, about 223 days between hard freezes, across 2K acres of town.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 28
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 6
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~223
- 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 7a is Opal's average, not your lot's — a low corner or a tree line moves it. Against Opal's 223-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Opal
Each reading below is measured for Opal itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredOpal runs about 223 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
MeasuredOpal 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 Opal is in
Opal sits in the Northern Piedmont — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Opal's own centroid rather than borrowed from Fauquier County.
What Grows in Opal
Every plant below cleared Opal's own zone 7a and its 223-day season. Each card opens that plant's Virginia profile. How we score.
Is it too late to plant in Opal?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Feb 28; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 28 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 6 — 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 Opal
Spotted lanternfly documented 5 miles from Opal, first recorded 2023. What to watch for.
What's on the federal record near Opal
Closest first, within ~10 miles of Opal. Listing isn't leaking, and distance isn't exposure.
- H and E W Long IncorporatedUnderground Storage Tanks · 2600 ft
- AMOCO OIL COUnderground Storage Tanks · 2600 ft
- COUNTRY STORE #4Underground Storage Tanks · 0.5 mi
- J. ARNOLD HELMUnderground Storage Tanks · 0.5 mi
- THE STOREUnderground Storage Tanks · 0.5 mi
- 48S 5BNitrate · 0.5 mi
- SHEETZ, INC. #221Brownfields · 0.6 mi
- Sheetz 221Underground Storage Tanks · 0.6 mi
- Opal Wi Not StopUnderground Storage Tanks · 0.6 mi
- Former Gas Station (1920's)Underground Storage Tanks · 0.6 mi
- 29 FOOD MARTUnderground Storage Tanks · 0.6 mi
- WALSHS EXXONUnderground Storage Tanks · 0.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Opal'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 Opal.
Total Sites
299
within ~10 miles of Opal
Risk Level
Elevated
Highest-severity
11 Toxics Release Inventory facilities
Sources Checked
within ~10 miles of Opal
Severity Distribution
within ~10 miles of Opal
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Opal, PFAS runs higher than the national average — 5 sites within ~10 miles of Opal. That's not a problem with your land — it's information about it.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check your specific parcel in Opal
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 Opal average
Your land is one point inside Opal
Everything above resolves to Opal 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 Opal Average
Opal Average
- ●USDA Zones 7a, averaged across Opal
- ●One soil character for all of Opal
- ●Frost dates read at Opal's scale: Mar 28 to Nov 6
YOUR Parcel
- ✓Your exact zone, not Opal's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Opal
Pull a site-specific report for your exact address in Opal, Virginia — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Opal averages can't show:
We read public map data around Opal — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Opal average
How we know this about Opal
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 Opal’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 Opal
When does frost risk typically end in Opal?
The last hard freeze (28°F) in Opal typically lands around Mar 28, 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 18.
When is the first frost in Opal?
The first hard freeze (28°F) in Opal typically arrives around Nov 6, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 23, so the watching starts about Oct 7 — about 223 days after the spring freeze cleared.
How long is the growing season in Opal?
Measured between 28°F hard freezes, Opal sees about 223 frost-free days — roughly Mar 28 through Nov 6, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 18 to Oct 23, about 188 days.
Is the soil safe to grow vegetables in Opal?
The federal record around Opal is a meaningful one — 299 documented sites, mostly Underground Storage Tanks entries (182), the nearest Underground Storage Tanks record about 0.5 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 Opal?
From about Oct 7 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 6 (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 6. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Opal's scale — its 7a band and its 223-day season. Your yard writes its own version of Opal'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 Opal’s own scale
7 of the readings below were taken at Opal's own scale — its own ~223-day season between 28°F freezes, the 2,008 acres it covers and 299 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Opal's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Opal's own 28°F hard-freeze dates, about Mar 28 and Nov 6 and the ~223-day span between themNOAA 1991–2020 Climate Normals
- 299 documented contamination sites on the federal record near Opal, the closest Underground Storage Tanks record about 0.5 miles out from the town centreFederal environmental registers
- Opal's boundary and the 2,008 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~223-day seasonGrowable Ground crop-matching engine
- The ecoregion at Opal's own centroid, the Northern PiedmontUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Opallydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Opal's 2,008 acres read through its county's SSURGO summaryfrom Fauquier County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Fauquier County
- The growing challenges every Virginia grower plans around — written at state scale, so they stay on the state guidefrom Virginia
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Fauquier County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Opal's 2,008 acreswhy one lot differs from the next →
- Which side of Opal you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,008 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.5 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 Opal-wide figureread your own land →