Harrisburg, Pennsylvania, sits in USDA hardiness zone 7a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
On paper, cabbage, hazelnut, california poppy, and collard greens all suit these conditions — on the ground, soil, sun, and drainage make the final call.
Even in Harrisburg, 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 Harrisburg 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 Harrisburg — soil, climate, flood, and parcel records. How we handle your address.
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Harrisburg — the short answer
Harrisburg, Pennsylvania: USDA zone 7a, about 225 days between hard freezes, across 5K acres of city.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 29
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 9
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~225
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 5K 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 Harrisburg's average, not your lot's — a low corner or a tree line moves it. Against Harrisburg's 225-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Harrisburg
Each reading below is measured for Harrisburg itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredHarrisburg runs about 225 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
MeasuredHarrisburg 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 Harrisburg is in
Harrisburg sits in the Ridge and Valley — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Harrisburg's own centroid rather than borrowed from Dauphin County.
What Grows in Harrisburg
Every plant below cleared Harrisburg's own zone 7a and its 225-day season. Each card opens that plant's Pennsylvania profile. How we score.
Is it too late to plant in Harrisburg?
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 Mar 1; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 29 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 9 — 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 Harrisburg
Spotted lanternfly documented 3 miles from Harrisburg, first recorded 2018. What to watch for.
What's on the federal record near Harrisburg
Closest first, within ~10 miles of Harrisburg. Listing isn't leaking, and distance isn't exposure.
- GOOD TIME ICEUnderground Storage Tanks · 250 ft
- HARGRO FLEXIBLE PACKAGING CORPToxics Release Inventory · 400 ft
- HARGRO FLEXIBLE PACK HBGUnderground Storage Tanks · 400 ft
- NEW FEDERAL COURTHOUSE BUILDING PROJECTBrownfields · 750 ft
- ZOMMIT CLNRUnderground Storage Tanks · 1100 ft
- GREYHOUND LINES INCUnderground Storage Tanks · 1200 ft
- KINGS FOOD MART 2Underground Storage Tanks · 1200 ft
- COOPERS BODY SHOPUnderground Storage Tanks · 1300 ft
- FIRE STA 1Underground Storage Tanks · 1300 ft
- MKT PLACE TOWNHOMESUnderground Storage Tanks · 1400 ft
- DOMESTIC LINEN SUPPLY COUnderground Storage Tanks · 1600 ft
- NORD PERLITE COUnderground Storage Tanks · 1700 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Harrisburg'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 Harrisburg.
Sources Checked
within ~10 miles of Harrisburg
Severity Distribution
within ~10 miles of Harrisburg
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.
- •On a private well, test for nitrates: above 10 mg/L the water needs treatment before irrigating.
Check your specific parcel in Harrisburg
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 Harrisburg average
Your land is one point inside Harrisburg
Everything above resolves to Harrisburg as a whole — one PHZM band and one 28°F frost record, read across 5K 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 city 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 Harrisburg Average
Harrisburg Average
- ●USDA Zones 7a, averaged across Harrisburg
- ●One soil character for all of Harrisburg
- ●Frost dates read at Harrisburg's scale: Mar 29 to Nov 9
YOUR Parcel
- ✓Your exact zone, not Harrisburg's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Harrisburg
Pull a site-specific report for your exact address in Harrisburg, Pennsylvania — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Harrisburg averages can't show:
We read public map data around Harrisburg — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Harrisburg average
How we know this about Harrisburg
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Harrisburg’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 city grain anywhere on this page — there is no city-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 Harrisburg
When does frost risk typically end in Harrisburg?
The last hard freeze (28°F) in Harrisburg typically lands around Mar 29, 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 19.
When is the first frost in Harrisburg?
The first hard freeze (28°F) in Harrisburg typically arrives around Nov 9, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 26, so the watching starts about Oct 10 — about 225 days after the spring freeze cleared.
How long is the growing season in Harrisburg?
Measured between 28°F hard freezes, Harrisburg sees about 225 frost-free days — roughly Mar 29 through Nov 9, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 19 to Oct 26, about 190 days.
Is the soil safe to grow vegetables in Harrisburg?
The federal record around Harrisburg is a meaningful one — 1,775 documented sites, mostly Underground Storage Tanks entries (1,063), the nearest Underground Storage Tanks record under a tenth of a mile 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 Harrisburg?
From about Oct 10 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 9 (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 9. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Harrisburg's scale — its 7a band and its 225-day season. Your yard writes its own version of Harrisburg'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 Harrisburg’s own scale
7 of the readings below were taken at Harrisburg's own scale — its own ~225-day season between 28°F freezes, the 5,196 acres it covers and 1,775 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Harrisburg's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Harrisburg's own 28°F hard-freeze dates, about Mar 29 and Nov 9 and the ~225-day span between themNOAA 1991–2020 Climate Normals
- 1,775 documented contamination sites on the federal record near Harrisburg, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Harrisburg's boundary and the 5,196 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~225-day seasonGrowable Ground crop-matching engine
- The ecoregion at Harrisburg's own centroid, the Ridge and ValleyUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Harrisburglydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Harrisburg's 5,196 acres read through its county's SSURGO summaryfrom Dauphin County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Dauphin 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 Dauphin County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Harrisburg's 5,196 acreswhy one lot differs from the next →
- Which side of Harrisburg you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 5,196 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record under a tenth of a mile 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 Harrisburg-wide figureread your own land →
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