Hamilton Square, 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.
The conditions favor cabbage, hazelnut, california poppy, and collard greens, among others — though every individual site edits that list with its own soil, sun, and drainage.
Even in Hamilton Square, 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 Hamilton Square 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 Hamilton Square — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Hamilton Square — the short answer
Hamilton Square, New Jersey: USDA zone 7a, about 222 days between hard freezes, across 3K 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 7
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~222
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 3K 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 Hamilton Square's average, not your lot's — a low corner or a tree line moves it. Against Hamilton Square's 222-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Hamilton Square
Each reading below is measured for Hamilton Square itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredHamilton Square runs about 222 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
MeasuredHamilton Square 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 Hamilton Square is in
Hamilton Square sits in the Atlantic Coastal Pine Barrens — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Hamilton Square's own centroid, and it is not what its county reads: Mercer County is mostly Northern Piedmont. The wider page above you is answering a different question about different ground.
What Grows in Hamilton Square
Every plant below cleared Hamilton Square's own zone 7a and its 222-day season. Each card opens that plant's New Jersey profile. How we score.
Is it too late to plant in Hamilton Square?
Rarely: the season closes in stages, not all at once, and each stage has its crops. 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 7 — 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 Hamilton Square
Spotted lanternfly documented 4 miles from Hamilton Square, first recorded 2019. What to watch for.
What's on the federal record near Hamilton Square
Closest first, within ~10 miles of Hamilton Square. Listing isn't leaking, and distance isn't exposure.
- NITTI'S SUBARU INCUnderground Storage Tanks · 400 ft
- HAMILTON SQUARE SHELLUnderground Storage Tanks · 1200 ft
- HAMILTON SUNOCOUnderground Storage Tanks · 1400 ft
- MODERN RENTALUnderground Storage Tanks · 2300 ft
- 210054-- Robrt Frost 10Nitrate · 0.5 mi
- TRENTON WATER WORKSPFAS · 0.5 mi
- WELL 10Underground Storage Tanks · 0.5 mi
- 210729-- ICP NU16Nitrate · 0.6 mi
- 56027 HAMILTON SQUARE FUELSUnderground Storage Tanks · 0.6 mi
- PETCO STORE #2873Brownfields · 0.7 mi
- SAKER SHOPRITE #566Brownfields · 0.7 mi
- 136 MERCER STUnderground Storage Tanks · 0.7 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Hamilton Square'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 Hamilton Square.
Total Sites
2,242
within ~10 miles of Hamilton Square
Risk Level
Elevated
Highest-severity
33 Superfund sites
Sources Checked
within ~10 miles of Hamilton Square
Severity Distribution
within ~10 miles of Hamilton Square
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Hamilton Square, Superfund runs higher than the national average — 33 sites within ~10 miles of Hamilton Square. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around 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 Hamilton Square
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 Hamilton Square average
Your land is one point inside Hamilton Square
Everything above resolves to Hamilton Square as a whole — one PHZM band and one 28°F frost record, read across 3K 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 Hamilton Square Average
Hamilton Square Average
- ●USDA Zones 7a, averaged across Hamilton Square
- ●One soil character for all of Hamilton Square
- ●Frost dates read at Hamilton Square's scale: Mar 30 to Nov 7
YOUR Parcel
- ✓Your exact zone, not Hamilton Square's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Hamilton Square
Pull a site-specific report for your exact address in Hamilton Square, New Jersey — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Hamilton Square averages can't show:
We read public map data around Hamilton Square — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Hamilton Square average
How we know this about Hamilton Square
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 Hamilton Square’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 Hamilton Square
When does frost risk typically end in Hamilton Square?
The last hard freeze (28°F) in Hamilton Square 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 Hamilton Square?
The first hard freeze (28°F) in Hamilton Square 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 222 days after the spring freeze cleared.
How long is the growing season in Hamilton Square?
Measured between 28°F hard freezes, Hamilton Square sees about 222 frost-free days — roughly Mar 30 through Nov 7, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer Apr 20 to Oct 24, about 187 days.
Is the soil safe to grow vegetables in Hamilton Square?
The federal record around Hamilton Square is a meaningful one — 2,242 documented sites, mostly Underground Storage Tanks entries (1,193), 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 Hamilton Square?
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 Hamilton Square's scale — its 7a band and its 222-day season. Your yard writes its own version of Hamilton Square'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 Hamilton Square’s own scale
7 of the readings below were taken at Hamilton Square's own scale — its own ~222-day season between 28°F freezes, the 2,737 acres it covers and 2,242 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Hamilton Square's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Hamilton Square's own 28°F hard-freeze dates, about Mar 30 and Nov 7 and the ~222-day span between themNOAA 1991–2020 Climate Normals
- 2,242 documented contamination sites on the federal record near Hamilton Square, the closest Underground Storage Tanks record under a tenth of a mile out from the town centreFederal environmental registers
- Hamilton Square's boundary and the 2,737 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~222-day seasonGrowable Ground crop-matching engine
- Hamilton Square sits in the Atlantic Coastal Pine Barrens — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Hamilton Squarelydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Hamilton Square's 2,737 acres read through its county's SSURGO summaryfrom Mercer County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Mercer 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 Mercer County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Hamilton Square's 2,737 acreswhy one lot differs from the next →
- Which side of Hamilton Square you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 2,737 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 Hamilton Square-wide figureread your own land →
More in New Jersey
Wider growing context
What grows across New JerseyHamilton Square sits outside our named growing regions, so New Jersey as a whole is its closest context here.
Nearby growing guides