Milton, New Hampshire, sits in USDA hardiness zone 5b — a band that supports both cool-season staples and warm-season crops chosen to fit the local frost window.
Growers here do well with cabbage, cranberry, lavender, and collard greens — with the usual caveat that any single yard's soil, sun, and drainage cast the deciding vote.
Even in Milton, 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 Milton 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 Milton — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Milton — the short answer
Milton, New Hampshire: USDA zone 5b, about 185 days between hard freezes, across 517 acres of town.
- USDA zone
- 5b
- 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 21
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~185
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Town area
- 517 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 5b is Milton's average, not your lot's — a low corner or a tree line moves it. Against Milton's 185-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Milton
Each reading below is measured for Milton itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredMilton runs about 185 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
MeasuredMilton sits in USDA hardiness zone 5b.
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 Milton is in
Milton sits in the Northeastern Highlands — EPA Level III, inside the wider Northern Forests. That is read at Milton's own centroid, and it is not what its county reads: Strafford County is mostly Northeastern Coastal Zone. The wider page above you is answering a different question about different ground.
What Grows in Milton
Every plant below cleared Milton's own zone 5b and its 185-day season. Each card opens that plant's New Hampshire profile. How we score.
Is it too late to plant in Milton?
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 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 21 — 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 Milton
Spotted lanternfly documented 20 miles from Milton, first recorded 2022. What to watch for.
What's on the federal record near Milton
Closest first, within ~10 miles of Milton. Listing isn't leaking, and distance isn't exposure.
- PIKE INDUSTRIES INCBrownfields · 2300 ft
- BROADVIEW VETERINARY GROUPBrownfields · 2600 ft
- CUMBERLAND FARMS 2822Underground Storage Tanks · 0.9 mi
- DOLLAR GENERAL STORE 16388Brownfields · 1.0 mi
- PIKE INDUSTRIES INC - FARMINGTON HMAToxics Release Inventory · 1.4 mi
- PIKE INDUSTRIES INC P913Underground Storage Tanks · 1.5 mi
- J & L REPAIRS LLCBrownfields · 1.5 mi
- VACHON APARTMENTSUnderground Storage Tanks · 1.9 mi
- MILTON LAKESIDE MARTUnderground Storage Tanks · 2.0 mi
- SPAULDING COMPOSITE CO FABRICATION DIVToxics Release Inventory · 2.1 mi
- FOREST PUMP CO INCUnderground Storage Tanks · 2.1 mi
- TILLOTSON HEALTHCARE CORPToxics Release Inventory · 2.1 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Milton'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 Milton.
Sources Checked
within ~10 miles of Milton
Severity Distribution
within ~10 miles of Milton
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Milton, two things run higher than the national average within ~10 miles of Milton — PFAS (3 sites) and Toxics Release Inventory (21 sites). That's not a problem with your land — it's information about it.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Toxics Release Inventory: TRI facilities report annual chemical releases to air, water, and land.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check prevailing wind direction — downwind parcels face higher exposure than upwind or crosswind locations.
Check your specific parcel in Milton
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 Milton average
Your land is one point inside Milton
Everything above resolves to Milton as a whole — one PHZM band and one 28°F frost record, read across 517 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 Milton Average
Milton Average
- ●USDA Zones 5b, averaged across Milton
- ●One soil character for all of Milton
- ●Frost dates read at Milton's scale: Apr 19 to Oct 21
YOUR Parcel
- ✓Your exact zone, not Milton's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Milton
Pull a site-specific report for your exact address in Milton, New Hampshire — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Milton averages can't show:
We read public map data around Milton — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Milton average
How we know this about Milton
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 Milton’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 Milton
When does frost risk typically end in Milton?
The last hard freeze (28°F) in Milton 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 Milton?
The first hard freeze (28°F) in Milton typically arrives around Oct 21, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 7, so the watching starts about Sep 21 — about 185 days after the spring freeze cleared.
How long is the growing season in Milton?
Measured between 28°F hard freezes, Milton sees about 185 frost-free days — roughly Apr 19 through Oct 21, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 10 to Oct 7, about 150 days.
Is the soil safe to grow vegetables in Milton?
The federal record around Milton runs heavier than most — 305 documented sites, mostly Underground Storage Tanks entries (162), the nearest Brownfields record about 0.4 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 Milton?
From about Sep 21 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 21 (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 21. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Milton's scale — its 5b band and its 185-day season. Your yard writes its own version of Milton'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 Milton’s own scale
7 of the readings below were taken at Milton's own scale — its own ~185-day season between 28°F freezes, the 517 acres it covers and 305 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Milton's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Milton's own 28°F hard-freeze dates, about Apr 19 and Oct 21 and the ~185-day span between themNOAA 1991–2020 Climate Normals
- 305 documented contamination sites on the federal record near Milton, the closest Brownfields record about 0.4 miles out from the town centreFederal environmental registers
- Milton's boundary and the 517 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~185-day seasonGrowable Ground crop-matching engine
- Milton sits in the Northeastern Highlands — not the ecoregion its county mostly readsUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Miltonlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Milton's 517 acres read through its county's SSURGO summaryfrom Strafford County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Strafford 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 Strafford County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Milton's 517 acreswhy one lot differs from the next →
- Which side of Milton you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 517 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Brownfields 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 Milton-wide figureread your own land →