Belfast, Maine, sits in USDA hardiness zone 5b — a zone band wide enough that plant choice, not possibility, is the interesting question.
Among the crops suited to this profile: cabbage, cranberry, lavender, and collard greens. The site-level story — soil, sun, drainage — decides the rest.
Even in Belfast, 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 Belfast 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 Belfast — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Belfast — the short answer
Belfast, Maine: USDA zone 5b, about 192 days between hard freezes, across 22K acres of city.
- USDA zone
- 5b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 18
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 27
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~192
- NOAA 1991–2020 Climate Normals, 28°F — this town
- City area
- 22K 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 Belfast's average, not your lot's — a low corner or a tree line moves it. Against Belfast's 192-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Belfast
Each reading below is measured for Belfast itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredBelfast runs about 192 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
MeasuredBelfast 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 Belfast is in
Belfast sits in the Acadian Plains and Hills — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Belfast's own centroid rather than borrowed from Waldo County.
What Grows in Belfast
Every plant below cleared Belfast's own zone 5b and its 192-day season. Each card opens that plant's Maine profile. How we score.
Is it too late to plant in Belfast?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Mar 21; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 18 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 27 — 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 Belfast
Survey cells within 31 miles of Belfast checked for spotted lanternfly, none carrying a detection — a surveyed negative, not an absence of looking. Nearest documented record 34 miles off. What to watch for.
What's on the federal record near Belfast
Closest first, within ~10 miles of Belfast. Listing isn't leaking, and distance isn't exposure.
- NICKERSONS EXXONUnderground Storage Tanks · 1000 ft
- CIRCLE K #7104Brownfields · 1000 ft
- CIRCLE K #7104Underground Storage Tanks · 1100 ft
- DUTCH CHEVROLET, BUICK, INC.Brownfields · 1300 ft
- AUTOZONE #3210Brownfields · 1600 ft
- STAG IV BELFAST UTILITY 3Underground Storage Tanks · 1700 ft
- BIG APPLE BELFASTUnderground Storage Tanks · 2000 ft
- MBNA BELFAST FLEET BLDGUnderground Storage Tanks · 2100 ft
- STAG IV BELFAST UTILITY 2Underground Storage Tanks · 2300 ft
- ATHEANAHEALTH INCUnderground Storage Tanks · 2300 ft
- O'REILLY AUTO PARTS #4520Brownfields · 2500 ft
- WENTWORTH FAMILY QUICK STOPUnderground Storage Tanks · 0.6 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Belfast'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 Belfast.
Total Sites
150
within ~10 miles of Belfast
Risk Level
Elevated
Highest-severity
2 Superfund sites (none NPL-listed)
Sources Checked
within ~10 miles of Belfast
Severity Distribution
within ~10 miles of Belfast
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Belfast, Underground Storage Tanks runs higher than the national average — 95 sites within ~10 miles of Belfast. It's not cause for alarm — it's worth knowing, and there's a sensible way to grow around it.
Underground Storage Tanks: Underground storage tanks are the single most common source of soil contamination near homes and gardens.
Use raised beds with imported soil — this eliminates the primary soil-contact pathway.
Check your specific parcel in Belfast
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 Belfast average
Your land is one point inside Belfast
Everything above resolves to Belfast as a whole — one PHZM band and one 28°F frost record, read across 22K 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 city 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 Belfast Average
Belfast Average
- ●USDA Zones 5b, averaged across Belfast
- ●One soil character for all of Belfast
- ●Frost dates read at Belfast's scale: Apr 18 to Oct 27
YOUR Parcel
- ✓Your exact zone, not Belfast's 5b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Belfast
Pull a site-specific report for your exact address in Belfast, Maine — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Belfast averages can't show:
We read public map data around Belfast — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Belfast average
How we know this about Belfast
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at this city’s own centroid; hard-freeze dates from NOAA 1991–2020 28°F normals at Belfast’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 city grain anywhere on this page — there is no city-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 Belfast
When does frost risk typically end in Belfast?
The last hard freeze (28°F) in Belfast typically lands around Apr 18, 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 9.
When is the first frost in Belfast?
The first hard freeze (28°F) in Belfast typically arrives around Oct 27, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 13, so the watching starts about Sep 27 — about 192 days after the spring freeze cleared.
How long is the growing season in Belfast?
Measured between 28°F hard freezes, Belfast sees about 192 frost-free days — roughly Apr 18 through Oct 27, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 9 to Oct 13, about 157 days.
Is the soil safe to grow vegetables in Belfast?
The federal record around Belfast is a meaningful one — 150 documented sites, mostly Underground Storage Tanks entries (95), the nearest Underground Storage Tanks record about 0.2 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 Belfast?
From about Sep 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 Oct 27 (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 27. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Belfast's scale — its 5b band and its 192-day season. Your yard writes its own version of Belfast'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 Belfast’s own scale
7 of the readings below were taken at Belfast's own scale — its own ~192-day season between 28°F freezes, the 21,793 acres it covers and 150 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Belfast's own USDA hardiness band, zones 5bUSDA PHZM 2023
- Belfast's own 28°F hard-freeze dates, about Apr 18 and Oct 27 and the ~192-day span between themNOAA 1991–2020 Climate Normals
- 150 documented contamination sites on the federal record near Belfast, the closest Underground Storage Tanks record about 0.2 miles out from the town centreFederal environmental registers
- Belfast's boundary and the 21,793 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 5b and a ~192-day seasonGrowable Ground crop-matching engine
- The ecoregion at Belfast's own centroid, the Acadian Plains and HillsUS EPA Level III Ecoregions
- Lanternfly survey cells around Belfast checked, none carrying a detectionlydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Belfast's 21,793 acres read through its county's SSURGO summaryfrom Waldo County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Waldo County
- The growing challenges every Maine grower plans around — written at state scale, so they stay on the state guidefrom Maine
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Waldo County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Belfast's 21,793 acreswhy one lot differs from the next →
- Which side of Belfast you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 21,793 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 0.2 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 Belfast-wide figureread your own land →
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