Darby, Pennsylvania, sits in USDA hardiness zone 7b — a range where zone-matched perennials and frost-aware annual timing set what succeeds.
Reliable performers under these conditions include cabbage, prickly pear, california poppy, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Darby, 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 Darby 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 Darby — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Darby — the short answer
Darby, Pennsylvania: USDA zone 7b, about 254 days between hard freezes, across 539 acres of town.
- USDA zone
- 7b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 17
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 26
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~254
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 539 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 7b is Darby's average, not your lot's — a low corner or a tree line moves it. Against Darby's 254-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Darby
Each reading below is measured for Darby itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredDarby runs about 254 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
MeasuredDarby 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 Darby is in
Darby sits in the Northern Piedmont — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Darby's own centroid rather than borrowed from Delaware County.
What Grows in Darby
Every plant below cleared Darby's own zone 7b and its 254-day season. Each card opens that plant's Pennsylvania profile. How we score.
Is it too late to plant in Darby?
Rarely: the season closes in stages, not all at once, and each stage has its crops. Cool-season crops can go in from around Feb 17; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 17 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 26 — 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 Darby
Spotted lanternfly documented 2 miles from Darby, first recorded 2017. What to watch for.
What's on the federal record near Darby
Closest first, within ~10 miles of Darby. Listing isn't leaking, and distance isn't exposure.
- TMI INCUnderground Storage Tanks · 600 ft
- MCGONIGLE AUTO REPAIRUnderground Storage Tanks · 600 ft
- PICKETTS AUTOUnderground Storage Tanks · 900 ft
- DARBY POST OFCUnderground Storage Tanks · 1100 ft
- CHARM 1HR CLNRSBrownfields · 1100 ft
- PENNWOOD WEST JR HIGH SCHUnderground Storage Tanks · 1100 ft
- PENN WOOD WEST JR HIGH SCHBrownfields · 1100 ft
- Z TASTE OF STATESUnderground Storage Tanks · 1200 ft
- FAMILY DOLLAR STORE NO 11761Brownfields · 1300 ft
- DELCO COLLISION CENTERBrownfields · 1500 ft
- CVS PHARMACY #0460Brownfields · 1600 ft
- SENTRY PAINT TECHToxics Release Inventory · 1600 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from Darby'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 Darby.
Sources Checked
within ~10 miles of Darby
Severity Distribution
within ~10 miles of Darby
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Darby, Superfund runs higher than the national average — 96 sites within ~10 miles of Darby. That's not a problem with your land — it's information about it.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check your specific parcel in Darby
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 Darby average
Your land is one point inside Darby
Everything above resolves to Darby as a whole — one PHZM band and one 28°F frost record, read across 539 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 Darby Average
Darby Average
- ●USDA Zones 7b, averaged across Darby
- ●One soil character for all of Darby
- ●Frost dates read at Darby's scale: Mar 17 to Nov 26
YOUR Parcel
- ✓Your exact zone, not Darby's 7b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Darby
Pull a site-specific report for your exact address in Darby, Pennsylvania — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Darby averages can't show:
We read public map data around Darby — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Darby average
How we know this about Darby
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 Darby’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 Darby
When does frost risk typically end in Darby?
The last hard freeze (28°F) in Darby typically lands around Mar 17, 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 7.
When is the first frost in Darby?
The first hard freeze (28°F) in Darby typically arrives around Nov 26, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Nov 12, so the watching starts about Oct 27 — about 254 days after the spring freeze cleared.
How long is the growing season in Darby?
Measured between 28°F hard freezes, Darby sees about 254 frost-free days — roughly Mar 17 through Nov 26, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 7 to Nov 12, about 219 days.
Is the soil safe to grow vegetables in Darby?
The federal record around Darby runs heavier than most — 5,163 documented sites, mostly Underground Storage Tanks entries (2,484), the nearest Underground Storage Tanks record about 0.1 miles out — so test the soil before planting food in the ground, and raised beds with clean imported soil grow well in the meantime. Even here, proximity to a documented site is information, not a diagnosis of any one yard; the contamination map shows exactly what's recorded and where.
How do I protect my plants from frost in Darby?
From about Oct 27 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 26 (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 26. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Darby's scale — its 7b band and its 254-day season. Your yard writes its own version of Darby'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 Darby’s own scale
7 of the readings below were taken at Darby's own scale — its own ~254-day season between 28°F freezes, the 539 acres it covers and 5,163 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Darby's own USDA hardiness band, zones 7bUSDA PHZM 2023
- Darby's own 28°F hard-freeze dates, about Mar 17 and Nov 26 and the ~254-day span between themNOAA 1991–2020 Climate Normals
- 5,163 documented contamination sites on the federal record near Darby, the closest Underground Storage Tanks record about 0.1 miles out from the town centreFederal environmental registers
- Darby's boundary and the 539 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7b and a ~254-day seasonGrowable Ground crop-matching engine
- The ecoregion at Darby's own centroid, the Northern PiedmontUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Darbylydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Darby's 539 acres read through its county's SSURGO summaryfrom Delaware County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Delaware 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 Delaware County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Darby's 539 acreswhy one lot differs from the next →
- Which side of Darby you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 539 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.1 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 Darby-wide figureread your own land →
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