South River, New Jersey, sits in USDA hardiness zone 7a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
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 South River, 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 South River 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 South River — soil, climate, flood, and parcel records. How we handle your address.
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South River — the short answer
South River, New Jersey: USDA zone 7a, about 225 days between hard freezes, across 2K acres of town.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Mar 30
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Nov 10
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~225
- 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 South River's average, not your lot's — a low corner or a tree line moves it. Against South River's 225-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in South River
Each reading below is measured for South River itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredSouth River 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
MeasuredSouth River 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 South River is in
South River sits in the Atlantic Coastal Pine Barrens — EPA Level III, inside the wider Eastern Temperate Forests. That is read at South River's own centroid rather than borrowed from Middlesex County.
What Grows in South River
Every plant below cleared South River's own zone 7a and its 225-day season. Each card opens that plant's New Jersey profile. How we score.
Is it too late to plant in South River?
Almost never — the real question is what to plant next. Cool-season crops can go in from around Mar 2; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Mar 30 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 10 — 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 South River
Spotted lanternfly documented 1 miles from South River, first recorded 2018. What to watch for.
What's on the federal record near South River
Closest first, within ~10 miles of South River. Listing isn't leaking, and distance isn't exposure.
- SOUTH RIVER W DEPTPFAS · 25 ft
- FIREHOUSE REDEVELOPMENT SITEUnderground Storage Tanks · 1000 ft
- IDM CORPUnderground Storage Tanks · 1200 ft
- JACKSON ST SEWAGE PUMP STATIUnderground Storage Tanks · 1400 ft
- 230440-- Ind 1Nitrate · 1400 ft
- T&Z AUTO SERVICEUnderground Storage Tanks · 1500 ft
- DA-GREEN ELECTRONICS LIMITEDUnderground Storage Tanks · 1500 ft
- BOROUGH MUNICIPAL OFFICEUnderground Storage Tanks · 1500 ft
- SOUTH RIVER STORAGEUnderground Storage Tanks · 1600 ft
- BUS BODY WORKSUnderground Storage Tanks · 1900 ft
- HMH JFK UNIV MEDICAL CENTER DCC/SOUTH RIVERBrownfields · 1900 ft
- STEVES AUTOUnderground Storage Tanks · 1900 ft
6 more sites are on the record inside the same radius. See them on the map
Measured from South River'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 South River.
Sources Checked
within ~10 miles of South River
Severity Distribution
within ~10 miles of South River
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around South River, two things run higher than the national average within ~10 miles of South River — Superfund (85 sites) and Toxics Release Inventory (251 sites). Knowing it is half the work — and it's nothing a thoughtful grower can't plan for.
Superfund: Superfund sites represent the most severe contamination in the federal system.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Check your specific parcel in South River
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 South River average
Your land is one point inside South River
Everything above resolves to South River 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 South River Average
South River Average
- ●USDA Zones 7a, averaged across South River
- ●One soil character for all of South River
- ●Frost dates read at South River's scale: Mar 30 to Nov 10
YOUR Parcel
- ✓Your exact zone, not South River's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in South River
Pull a site-specific report for your exact address in South River, New Jersey — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that South River averages can't show:
We read public map data around South River — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the South River average
How we know this about South River
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 South River’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 South River
When does frost risk typically end in South River?
The last hard freeze (28°F) in South River typically lands around Mar 30, 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 20.
When is the first frost in South River?
The first hard freeze (28°F) in South River typically arrives around Nov 10, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 27, so the watching starts about Oct 11 — about 225 days after the spring freeze cleared.
How long is the growing season in South River?
Measured between 28°F hard freezes, South River sees about 225 frost-free days — roughly Mar 30 through Nov 10, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 20 to Oct 27, about 190 days.
Is the soil safe to grow vegetables in South River?
The federal record around South River runs heavier than most — 3,645 documented sites, mostly Underground Storage Tanks entries (1,868), the nearest PFAS record under a tenth of a mile 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 South River?
From about Oct 11 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 10 (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 10. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at South River's scale — its 7a band and its 225-day season. Your yard writes its own version of South River'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 South River’s own scale
7 of the readings below were taken at South River's own scale — its own ~225-day season between 28°F freezes, the 1,782 acres it covers and 3,645 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- South River's own USDA hardiness band, zones 7aUSDA PHZM 2023
- South River's own 28°F hard-freeze dates, about Mar 30 and Nov 10 and the ~225-day span between themNOAA 1991–2020 Climate Normals
- 3,645 documented contamination sites on the federal record near South River, the closest PFAS record under a tenth of a mile out from the town centreFederal environmental registers
- South River's boundary and the 1,782 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 South River's own centroid, the Atlantic Coastal Pine BarrensUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of South Riverlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so South River's 1,782 acres read through its county's SSURGO summaryfrom Middlesex County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Middlesex County
- The growing challenges every New Jersey grower plans around — written at state scale, so they stay on the state guidefrom New Jersey
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Middlesex County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among South River's 1,782 acreswhy one lot differs from the next →
- Which side of South River you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,782 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest PFAS 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 South River-wide figureread your own land →
More in New Jersey
Wider growing context
What grows across New JerseySouth River sits outside our named growing regions, so New Jersey as a whole is its closest context here.
Nearby growing guides