New Boston, New Hampshire, sits in USDA hardiness zone 6a — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
These conditions suit cabbage, hazelnut, lavender, and collard greens — a starting list any specific site will trim or extend with its own soil, sun, and drainage.
Even in New Boston, 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 New Boston 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 New Boston — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
New Boston — the short answer
New Boston, New Hampshire: USDA zone 6a, about 186 days between hard freezes, across 330 acres of town.
- USDA zone
- 6a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 19
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 22
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~186
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 330 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 6a is New Boston's average, not your lot's — a low corner or a tree line moves it. Against New Boston's 186-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in New Boston
Each reading below is measured for New Boston itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredNew Boston runs about 186 days between hard freezes — a moderate growing season.
There is room for the full run of cool-season crops plus a warm-season main crop, but the calendar is tight enough that a late spring or early fall frost still decides how much finishes.
Time warm-season transplants to your last hard freeze, and a few weeks of season extension turns a near-miss harvest into a sure one.
NOAA 1991–2020 Climate Normals
Winter hardiness
MeasuredNew Boston sits in USDA hardiness zone 6a.
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 New Boston is in
New Boston sits in the Northeastern Highlands — EPA Level III, inside the wider Northern Forests. That is read at New Boston's own centroid rather than borrowed from Hillsborough County.
What Grows in New Boston
Every plant below cleared New Boston's own zone 6a and its 186-day season. Each card opens that plant's New Hampshire profile. How we score.
Is it too late to plant in New Boston?
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 22; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 19 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 22 — long-season crops need about 90 days of runway, quick greens only 30. The tail of the season still works: sixty-day crops into late summer, quick greens after, garlic last of all.
Documented around New Boston
Spotted lanternfly documented 25 miles from New Boston, first recorded 2021. What to watch for.
What's on the federal record near New Boston
Closest first, within ~10 miles of New Boston. Listing isn't leaking, and distance isn't exposure.
- NH-NCW 99Nitrate · 2200 ft
- DANIELS OIL COUnderground Storage Tanks · 2500 ft
- NH-NCW 3Nitrate · 0.6 mi
- NEW BOSTON HIGHWAY DEPTUnderground Storage Tanks · 0.6 mi
- MANSFIELD BUS LINESUnderground Storage Tanks · 0.9 mi
- NH-NCW 8Nitrate · 1.9 mi
- FORMER BARSS CONVENIENCE STOREUnderground Storage Tanks · 3.0 mi
- SKVERIANUnderground Storage Tanks · 3.8 mi
- NEW BOSTON AIR FORCE STATIONBrownfields · 3.9 mi
- NH-NCW 2Nitrate · 3.9 mi
- NH-FCW 3Nitrate · 4.0 mi
- BRAZECOM INDUSTRIES LLCBrownfields · 4.0 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from New Boston'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 New Boston.
Sources Checked
within ~10 miles of New Boston
Severity Distribution
within ~10 miles of New Boston
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around New Boston, two things run higher than the national average within ~10 miles of New Boston — Superfund (8 sites) and Nitrate (162 sites). 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.
Nitrate: Nitrate contamination primarily comes from agricultural fertilizer runoff and failing septic systems.
Commission professional soil testing before any food production (test for heavy metals, VOCs, and SVOCs).
Test well water for nitrate if you rely on a private well for irrigation (EPA standard: 10 mg/L).
Check your specific parcel in New Boston
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 New Boston average
Your land is one point inside New Boston
Everything above resolves to New Boston as a whole — one PHZM band and one 28°F frost record, read across 330 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 New Boston Average
New Boston Average
- ●USDA Zones 6a, averaged across New Boston
- ●One soil character for all of New Boston
- ●Frost dates read at New Boston's scale: Apr 19 to Oct 22
YOUR Parcel
- ✓Your exact zone, not New Boston's 6a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in New Boston
Pull a site-specific report for your exact address in New Boston, New Hampshire — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that New Boston averages can't show:
We read public map data around New Boston — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the New Boston average
How we know this about New Boston
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 New Boston’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 New Boston
When does frost risk typically end in New Boston?
The last hard freeze (28°F) in New Boston typically lands around Apr 19, 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 May 10.
When is the first frost in New Boston?
The first hard freeze (28°F) in New Boston typically arrives around Oct 22, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 8, so the watching starts about Sep 22 — about 186 days after the spring freeze cleared.
How long is the growing season in New Boston?
Measured between 28°F hard freezes, New Boston sees about 186 frost-free days — roughly Apr 19 through Oct 22, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 10 to Oct 8, about 151 days.
Is the soil safe to grow vegetables in New Boston?
The federal record around New Boston is a meaningful one — 394 documented sites, mostly Nitrate entries (162), the nearest Nitrate record about 0.4 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 New Boston?
From about Sep 22 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 Oct 22 (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 Oct 22. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at New Boston's scale — its 6a band and its 186-day season. Your yard writes its own version of New Boston'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 New Boston’s own scale
7 of the readings below were taken at New Boston's own scale — its own ~186-day season between 28°F freezes, the 330 acres it covers and 394 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- New Boston's own USDA hardiness band, zones 6aUSDA PHZM 2023
- New Boston's own 28°F hard-freeze dates, about Apr 19 and Oct 22 and the ~186-day span between themNOAA 1991–2020 Climate Normals
- 394 documented contamination sites on the federal record near New Boston, the closest Nitrate record about 0.4 miles out from the town centreFederal environmental registers
- New Boston's boundary and the 330 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6a and a ~186-day seasonGrowable Ground crop-matching engine
- The ecoregion at New Boston's own centroid, the Northeastern HighlandsUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of New Bostonlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so New Boston's 330 acres read through its county's SSURGO summaryfrom Hillsborough County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Hillsborough County
- The growing challenges every New Hampshire grower plans around — written at state scale, so they stay on the state guidefrom New Hampshire
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Hillsborough County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among New Boston's 330 acreswhy one lot differs from the next →
- Which side of New Boston you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 330 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Nitrate record about 0.4 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 New Boston-wide figureread your own land →