Harmony, Rhode Island, sits in USDA hardiness zone 6b — enough range to grow cool-season vegetables, hardy fruit, and warm-season crops that mature before the first hard frost.
Reliable performers under these conditions include cabbage, hazelnut, lavender, and collard greens; what your own ground favors still comes down to its soil, sun, and drainage.
Even in Harmony, 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 Harmony 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 Harmony — soil, climate, flood, and parcel records. How we handle your address.
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Harmony — the short answer
Harmony, Rhode Island: USDA zone 6b, about 203 days between hard freezes, across 2K acres of town.
- USDA zone
- 6b
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 10
- NOAA 1991–2020 Climate Normals, 28°F — this town
- First hard freeze (28°F)
- Oct 30
- NOAA 1991–2020 Climate Normals, 28°F — this town
- Days between freezes
- ~203
- 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 6b is Harmony's average, not your lot's — a low corner or a tree line moves it. Against Harmony's 203-day season, see what your own ground reads.
Soil varies lot by lot — soil types explained.
What this means for growing in Harmony
Each reading below is measured for Harmony itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Season length
MeasuredHarmony runs about 203 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
MeasuredHarmony sits in USDA hardiness zone 6b.
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 Harmony is in
Harmony sits in the Northeastern Coastal Zone — EPA Level III, inside the wider Eastern Temperate Forests. That is read at Harmony's own centroid rather than borrowed from Providence County.
What Grows in Harmony
Every plant below cleared Harmony's own zone 6b and its 203-day season. Each card opens that plant's Rhode Island profile. How we score.
Is it too late to plant in Harmony?
Usually not — gardeners here simply switch what goes in the ground as the season moves. Cool-season crops can go in from around Mar 13; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 10 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Oct 30 — long-season crops need about 90 days of runway, quick greens only 30. With a season this long, “too late” mostly means “switch crops” — second sowings and a full fall garden are the norm, with garlic closing the year.
Documented around Harmony
Spotted lanternfly documented 4 miles from Harmony, first recorded 2022. What to watch for.
What's on the federal record near Harmony
Closest first, within ~10 miles of Harmony. Listing isn't leaking, and distance isn't exposure.
- HARMONY FIRE DISTRICT DEPARTMENTUnderground Storage Tanks · 1.1 mi
- COOPER ROAD/ PUTNAM PIKE AREASuperfund · 1.1 mi
- RI D O T MAINTENANCE DIVBrownfields · 1.1 mi
- DAVIS (GSR) LANDFILLSuperfund · 1.6 mi
- GLOCESTER GARAGE (D.O.T.)Underground Storage Tanks · 1.7 mi
- TOURBILLON TRAILER SALES INCBrownfields · 1.7 mi
- RI-GLW 28Nitrate · 1.8 mi
- E & I INC.Underground Storage Tanks · 2.0 mi
- UNDERGROUND CHOPPER INCBrownfields · 2.0 mi
- FOGARTY MEMORIAL SCHOOLUnderground Storage Tanks · 2.0 mi
- CONNETTI ENTERPRISES, INC.Underground Storage Tanks · 2.1 mi
- STEERE ORCHARDSUnderground Storage Tanks · 2.2 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Harmony'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 Harmony.
Sources Checked
within ~10 miles of Harmony
Severity Distribution
within ~10 miles of Harmony
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Harmony, two things run higher than the national average within ~10 miles of Harmony — Superfund (46 sites) and Toxics Release Inventory (104 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 Harmony
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 Harmony average
Your land is one point inside Harmony
Everything above resolves to Harmony 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 Harmony Average
Harmony Average
- ●USDA Zones 6b, averaged across Harmony
- ●One soil character for all of Harmony
- ●Frost dates read at Harmony's scale: Apr 10 to Oct 30
YOUR Parcel
- ✓Your exact zone, not Harmony's 6b
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your specific parcel in Harmony
Pull a site-specific report for your exact address in Harmony, Rhode Island — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Harmony averages can't show:
We read public map data around Harmony — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Harmony average
How we know this about Harmony
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 Harmony’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 Harmony
When does frost risk typically end in Harmony?
The last hard freeze (28°F) in Harmony typically lands around Apr 10, 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 1.
When is the first frost in Harmony?
The first hard freeze (28°F) in Harmony typically arrives around Oct 30, per NOAA 1991–2020 climate normals — the point tender summer crops finish. Lighter frosts run ahead of it, near Oct 16, so the watching starts about Sep 30 — about 203 days after the spring freeze cleared.
How long is the growing season in Harmony?
Measured between 28°F hard freezes, Harmony sees about 203 frost-free days — roughly Apr 10 through Oct 30, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 1 to Oct 16, about 168 days.
Is the soil safe to grow vegetables in Harmony?
The federal record around Harmony runs heavier than most — 1,498 documented sites, mostly Underground Storage Tanks entries (740), the nearest Underground Storage Tanks record about 1.1 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 Harmony?
From about Sep 30 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 30 (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 30. Hardy greens and roots shrug off light frost and sweeten after it — leave them in.
Everything above is measured at Harmony's scale — its 6b band and its 203-day season. Your yard writes its own version of Harmony'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 Harmony’s own scale
7 of the readings below were taken at Harmony's own scale — its own ~203-day season between 28°F freezes, the 1,884 acres it covers and 1,498 documented sites around it; 4 are borrowed from a wider read, named and linked below.
Measured here
- Harmony's own USDA hardiness band, zones 6bUSDA PHZM 2023
- Harmony's own 28°F hard-freeze dates, about Apr 10 and Oct 30 and the ~203-day span between themNOAA 1991–2020 Climate Normals
- 1,498 documented contamination sites on the federal record near Harmony, the closest Underground Storage Tanks record about 1.1 miles out from the town centreFederal environmental registers
- Harmony's boundary and the 1,884 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 6b and a ~203-day seasonGrowable Ground crop-matching engine
- The ecoregion at Harmony's own centroid, the Northeastern Coastal ZoneUS EPA Level III Ecoregions
- A documented spotted-lanternfly record within reach of Harmonylydemapr (De Bona & Helmus), 10 km survey lattice
Inherited from a wider read
- Soil character — no town-scale survey exists, so Harmony's 1,884 acres read through its county's SSURGO summaryfrom Providence County
- Growing-degree days and winter chill — measured county-wide only, so the county page carries themfrom Providence County
- The growing challenges every Rhode Island grower plans around — written at state scale, so they stay on the state guidefrom Rhode Island
- Butterfly and beetle records, and the farmland pesticide estimate — all published county-widefrom Providence County
What this page can’t tell you
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Harmony's 1,884 acreswhy one lot differs from the next →
- Which side of Harmony you're on — a low spot frosts first and a south wall warms early, and one normal is being asked to speak for all 1,884 acresreading your own microclimate →
- How close that record sits to YOUR lot — the closest Underground Storage Tanks record about 1.1 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 Harmony-wide figureread your own land →
More in Rhode Island
Wider growing context
What grows across Rhode IslandHarmony sits outside our named growing regions, so Rhode Island as a whole is its closest context here.
Nearby growing guides