Jefferson Hills, Pennsylvania, sits in USDA hardiness zone 6b — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Reliable performers under these conditions include cabbage, hazelnut, lavender, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Jefferson Hills, 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 Jefferson Hills 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 Jefferson Hills — soil, climate, flood, and parcel records. How we handle your address.
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Jefferson Hills — the short answer
Jefferson Hills, Pennsylvania: USDA zone 6b, about 217 days between hard freezes, across 11K acres of town.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 4
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 7
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~217
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 11K 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 6b is Jefferson Hills's average, not your lot's — a low corner or a tree line moves it. Against Jefferson Hills's 217-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Jefferson Hills
Each reading below is measured for Jefferson Hills itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredJefferson Hills runs about 217 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
MeasuredJefferson Hills sits in USDA hardiness zone 6b.
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 Jefferson Hills is in
Jefferson Hills sits in the Western Allegheny Plateau — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Jefferson Hills's own centroid rather than borrowed from Allegheny County.
What Grows in Jefferson Hills
Every plant below cleared Jefferson Hills's own zone 6b and its 217-day season. Each card opens that plant's Pennsylvania profile. How we score.
Is it too late to plant in Jefferson Hills?
For most of the year, no — what changes is which crops still fit the days remaining. Cool-season crops can go in from around Mar 7; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 4 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 7 — long-season crops need about 90 days of runway, quick greens only 30. With a season this long, “too late” mostly means “switch crops” — second sowings and a full fall garden are the norm, with garlic closing the year.
Documented around Jefferson Hills
Spotted lanternfly documented 4 miles from Jefferson Hills, first recorded 2018. What to watch for.
What's on the federal record near Jefferson Hills
Closest first, within ~10 miles of Jefferson Hills. Listing isn't leaking, and distance isn't exposure.
- WEST JEFFERSON HILLS MAINT BLDGUnderground Storage Tanks · 1600 ft
- SUPER AMER 5318Underground Storage Tanks · 0.7 mi
- LARGE SUNOCOUnderground Storage Tanks · 0.7 mi
- D D AUTO BODYBrownfields · 1.0 mi
- FERGUSON AUTO BODYBrownfields · 1.1 mi
- FINE LINE PAINTINGBrownfields · 1.1 mi
- THOMAS JEFFERSON HSBrownfields · 1.1 mi
- ESSOUnderground Storage Tanks · 1.2 mi
- JEFFERSON BORO ALLEGHENY CNTYUnderground Storage Tanks · 1.2 mi
- RALPH ZIMMERMAN EXCAVATING INCUnderground Storage Tanks · 1.2 mi
- PA TURNPIKE FAC JEFFERSON HILLS MAINTBrownfields · 1.3 mi
- TYK AMER/LARGEToxics Release Inventory · 1.3 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Jefferson Hills'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 Jefferson Hills.
Total Sites
1,812
within ~10 miles of Jefferson Hills
Risk Level
Elevated
Highest-severity
12 Superfund sites
Sources Checked
within ~10 miles of Jefferson Hills
Severity Distribution
within ~10 miles of Jefferson Hills
Highest-Severity Sites
Know Before You Grow
- •Underground tanks leak petroleum as they age — near a former filling station, test the soil.
- •Near a brownfield, raised beds of imported soil give your food clean ground.
- •TRI facilities report what they release. Check the wind — downwind beds catch more of it.
Check your specific parcel in Jefferson Hills
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 Jefferson Hills average
Your land is one point inside Jefferson Hills
Everything above resolves to Jefferson Hills as a whole — one PHZM band and one 28°F frost record, read across 11K 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 Jefferson Hills Average
Jefferson Hills Average
- ●USDA Zones 6b, averaged across Jefferson Hills
- ●One soil character for all of Jefferson Hills
- ●Frost dates read at Jefferson Hills's scale: Apr 4 to Nov 7
YOUR Parcel
- ✓Your exact zone, not Jefferson Hills's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Jefferson Hills
Pull a site-specific report for your exact address in Jefferson Hills, Pennsylvania — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Jefferson Hills averages can't show:
We read public map data around Jefferson Hills — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Jefferson Hills average
How we know this about Jefferson Hills
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 Jefferson Hills’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 Jefferson Hills
When does frost risk typically end in Jefferson Hills?
The last hard freeze (28°F) in Jefferson Hills typically lands around Apr 4, 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 25.
When is the first frost in Jefferson Hills?
The first hard freeze (28°F) in Jefferson Hills typically arrives around Nov 7, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 24, so the watching starts about Oct 8 — about 217 days after the spring freeze cleared.
How long is the growing season in Jefferson Hills?
Measured between 28°F hard freezes, Jefferson Hills sees about 217 frost-free days — roughly Apr 4 through Nov 7, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 25 to Oct 24, about 182 days.
Is the soil safe to grow vegetables in Jefferson Hills?
The federal record around Jefferson Hills is a meaningful one — 1,812 documented sites, mostly Underground Storage Tanks entries (917), the nearest Underground Storage Tanks record about 0.3 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 Jefferson Hills?
From about Oct 8 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 7 (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 7. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Jefferson Hills's scale — its 6b band and its 217-day season. Your yard writes its own version of Jefferson Hills'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 Jefferson Hills’s own scale
7 of the readings below were taken at Jefferson Hills's own scale — its own ~217-day season between 28°F freezes, the 10,614 acres it covers and 1,812 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Jefferson Hills's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Jefferson Hills's own 28°F hard-freeze dates, about Apr 4 and Nov 7 and the ~217-day span between themNOAA 1991–2020 Climate Normals
- 1,812 documented contamination sites on the federal record near Jefferson Hills, the closest Underground Storage Tanks record about 0.3 miles out from the town centreFederal environmental registers
- Jefferson Hills's boundary and the 10,614 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~217-day seasonGrowable Ground crop-matching engine
- The ecoregion at Jefferson Hills's own centroid, the Western Allegheny PlateauUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Jefferson Hillslydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Jefferson Hills's 10,614 acres read through its county's SSURGO summaryfrom Allegheny County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Allegheny County
- The growing challenges every Pennsylvania grower plans around — written at state scale, so they stay on the state guidefrom Pennsylvania
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Allegheny County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Jefferson Hills's 10,614 acreswhy one lot differs from the next →
- Which side of Jefferson Hills you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 10,614 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.3 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 Jefferson Hills-wide figureread your own land →