Plymouth County, in Massachusetts, sits in USDA hardiness zone 7a — room for a real mix of vegetables, fruit, and perennials matched to the local frost calendar.
Expect cabbage, pawpaw, california poppy, and collard greens to be strong candidates here; the deciding factors on any one parcel stay local — soil, sun, and drainage.
Grounded in USDA PHZM 2023 · Growable Ground suitability scoring · NOAA 1991–2020 Climate Normals
You’re in South Shore
The coastal band south of Boston into old cranberry country — sandy, acidic ground and a maritime season that runs a touch longer than the interior. Bog and shoreline shape what has always grown well down here.
Plymouth County holds more than one microclimate.
Soils and elevations shift across Plymouth County, so your frost dates and drainage aren't the county average. 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 Plymouth County — soil, climate, flood, and parcel records. How we handle your address.
No card required · your full report in seconds
Plymouth County — the short answer
Plymouth County, Massachusetts: USDA zone 7a, about 207 days between hard freezes, across 421K acres.
- USDA zone
- 7a
- USDA PHZM 2023
- Last hard freeze (28°F)
- Apr 11
- NOAA 1991–2020 Climate Normals, 28°F
- First hard freeze (28°F)
- Nov 4
- NOAA 1991–2020 Climate Normals, 28°F
- Days between freezes
- ~207
- NOAA 1991–2020 Climate Normals, 28°F
- County area
- 421K acres
- US Census TIGER/Line 2025
Every figure names the dataset it came from. Hard-freeze dates are county 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 Plymouth County's average, not your lot's — a low corner or a tree line moves it. Against Plymouth County's 207-day season, see what your own ground reads.
Heat in Plymouth County
Across a year, Plymouth County accumulates about 2,642 growing degree days above 50°F, about 116 more than the middle Massachusetts county — ahead of 9 of Massachusetts’s 14 counties. Degree days are the heat a crop actually gets to work with — more of them is more room to ripen a long-season crop before the freeze closes the window.
Grounded in PRISM Climate Group, Oregon State University — 1991–2020 monthly normals
Soil in Plymouth County
Across Plymouth County, the ground is predominantly Entisols, where Carver, Freetown, and Plymouth are the most extensive named soil series. The soil is generally excessively drained with a fine sandy loam surface. Topsoil pH runs about 4.2–5.2, very strongly acidic. Rainfall drains through hydrologic group A soils.
Soil order
Entisols
Drainage
Excessively drained
Prime farmland
11%
Hydric soils
30%
Soil still varies lot by lot — soil types explained.
How the ground varies across Plymouth County
The USDA soil survey maps 27% of Plymouth County as excessively drained — but another 61% drains differently: 18% moderately well drained, 17% very poorly drained.
Carver is the most extensive named soil at 14% of mapped acres, then Freetown (7%) and Plymouth (6%).
Which of them your own lot sits on is a parcel question, not a county one. Check your address for the survey at your boundary.
What this means for growing in Plymouth County
Each reading below is measured for Plymouth County itself — here is what it means for a garden here, and the move an experienced grower makes about it.
Drainage
MeasuredThe dominant soils across Plymouth County are excessively drained, in hydrologic group A — ground that drains quickly.
The upside is soil you can work early in spring and roots that never drown; the cost is that fast-draining ground dries out fast and leaches nutrients away before plants can use them.
Work in compost and mulch to hold moisture and feed, and water more often in short doses than deep and rarely.
USDA NRCS SSURGO
Surface pH
MeasuredTopsoil across Plymouth County runs about pH 4.2–5.2, on the acidic side.
Blueberries, potatoes, and rhododendrons thrive in it, but most vegetables start locking out nutrients below about pH 6.0 and grow pale and stunted no matter how much you feed them.
A measured lime application raises pH for the crops that need it — but test first, because the right rate depends on your own soil, not the county average.
USDA NRCS SSURGO
Wet ground
MeasuredAbout 30% of Plymouth County is mapped as hydric — wetland — soil.
If your lot falls in one of those pockets, a standard in-ground bed will fight waterlogging all season, and roots that need air will struggle.
Check how your own ground drains before you dig; raised beds or moisture-loving plantings turn a wet corner from a problem into a niche.
USDA NRCS SSURGO
Season length
MeasuredPlymouth County runs about 207 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
The kind of country Plymouth County is in
Plymouth County spans 2 EPA Level III ecoregions — Northeastern Coastal Zone (74%) and Atlantic Coastal Pine Barrens (26%). Which one your land falls in changes what grows wild there and how the ground behaves, and a county-wide answer cannot tell you which.
What Grows in Plymouth County
We scored all 1,086 plants against Plymouth County's own USDA zone 7a and its own 207-day season between hard freezes, using the same matching engine that runs a full parcel report. These cleared both. Sun, soil pH and drainage vary lot by lot — those are the parcel questions below. Each card opens that plant's Massachusetts profile.
Is it too late to plant in Plymouth County?
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 14; tender transplants wait until two to three weeks after the last 28°F hard freeze, which lands near Apr 11 (NOAA 1991–2020 climate normals); and from midsummer, planting counts back from the first fall freeze around Nov 4 — 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 Plymouth County
Spotted lanternfly documented 10 miles from Plymouth County, first recorded 2023. What to watch for.
- Japanese beetle26 documented records
- monarch butterfly223 documented records
Sighting records, so they follow observers as much as insects.
What gets applied to farmland in Plymouth County
USGS estimates 293 lb of Glyphosate on Plymouth County farmland in 2019, its largest by weight, ahead of Metolachlor & Metolachlor-s (237 lb) and Metolachlor-s (189 lb).
Farmland across the whole county, not any one lot. Check your address for the site-by-site record.
Safe to Grow Here?
What the federal record shows across Plymouth County — and how to grow with it.
We checked the federal record across Plymouth County — 2,727 documented sites across 6 of the 9 source types we track.
The most significant on record: 26 Superfund sites. Sites tracked in EPA's Superfund program — from assessment-stage CERCLIS entries to confirmed National Priorities List cleanup sites.
Plymouth County carries one of the heavier federal records we track — and that's not a verdict on your yard. Proximity to a documented site is information, not a diagnosis: nothing here says any particular parcel is affected. It does earn one concrete step — before food beds go in the ground, a professional soil test tells you exactly what you're working with, and raised beds with clean imported soil grow well almost anywhere in the meantime.
Sources: EPA, USGS — 1.8M documented sites tracked nationwide across 9 federal source types.
What's on the federal record near Plymouth County
Closest first, across Plymouth County. Listing isn't leaking, and distance isn't exposure.
- KINGSTON WATER DEPARTMENTPFAS · 25 ft
- MA-KGW 59 KINGSTON, MANitrate · 2100 ft
- CATON CONNECTOR CORPBrownfields · 0.5 mi
- CUMBERLAND FARMS #2183Underground Storage Tanks · 0.5 mi
- AUTOKOLOURBrownfields · 0.6 mi
- CUMBERLAND FARMS INCBrownfields · 0.6 mi
- INDIAN POND COUNTRY CLUBBrownfields · 0.6 mi
- KINGSTON HGW DEPT TOWN OFBrownfields · 0.7 mi
- TOWN OF KINGSTON HIGHWAY DEPTUnderground Storage Tanks · 0.7 mi
- NEWCOMB HEATINGBrownfields · 0.8 mi
- A T SERVICESBrownfields · 0.8 mi
- SHIRETOWN TRANSPROTATION COUnderground Storage Tanks · 0.8 mi
6 more sites are on the record inside the same radius. See them on the map
Measured from Plymouth County'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 Plymouth County.
Sources Checked
across Plymouth County
Severity Distribution
across Plymouth County
Highest-Severity Sites
A note from Gnorman
What an experienced grower watches for around here
In and around Plymouth County, two things run higher than the national average across Plymouth County — Brownfields (1,557 sites) and PFAS (26 sites). That's not a problem with your land — it's information about it.
Brownfields: Brownfield sites are former commercial or industrial properties where legacy soil contamination (heavy metals, PAHs, petroleum compounds) may persist.
PFAS: PFAS (per- and polyfluoroalkyl substances) are called "forever chemicals" because they do not biodegrade.
Check EPA brownfield remediation status — many sites have completed cleanup with institutional controls.
Test irrigation water source — this is the primary pathway for PFAS to reach garden crops.
Check your specific parcel in Plymouth County
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 Plymouth County average
Your land is one point inside Plymouth County
Everything above resolves to Plymouth County as a whole — one PHZM band and one county frost record, read across 421K 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 county 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 county average.
Your Lot vs the Plymouth County Average
Plymouth County Average
- ●USDA Zones 7a, averaged across Plymouth County
- ●One soil character for all of Plymouth County
- ●Frost dates read at Plymouth County's scale: Apr 11 to Nov 4
YOUR Parcel
- ✓Your exact zone, not Plymouth County's 7a
- ✓Your SSURGO soil type & pH
- ✓Your sun exposure, cast in 3D
See MY Growing Report
Read your parcel in Plymouth County
Pull a site-specific report for your exact address in Plymouth County, Massachusetts — soil, sun, drainage, frost risk, and scored plant recommendations.
Three things about your lot that Plymouth County averages can't show:
We read public map data around Plymouth County — soil, climate, flood, and parcel records. How we handle your address.
25+ data sources read at your address, not the Plymouth County average
How we know this about Plymouth County
The datasets: hardiness from the USDA ARS Plant Hardiness Zone Map 2023, read at county grain; hard-freeze dates from NOAA 1991–2020 28°F normals at this county’s own record where one resolves, and the labelled statewide window where none does; soils from the USDA NRCS SSURGO survey, area-weighted across the county’s own map units; boundaries and acreage from US Census TIGER/Line 2025; the contamination and pesticide records from the federal sources named in their beats above. Where Plymouth County carries no record of its own, the figure is inherited and labelled — the resolution ledger below names each.
Common questions about Plymouth County
When does frost risk typically end in Plymouth County?
The last hard freeze (28°F) in Plymouth County typically lands around Apr 11, 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 2.
How long is the growing season in Plymouth County?
Measured between 28°F hard freezes, Plymouth County sees about 207 frost-free days — roughly Apr 11 through Nov 4, per NOAA 1991–2020 climate normals. Tender crops work a shorter one: nearer May 2 to Oct 21, about 172 days.
Is the soil safe to grow vegetables in Plymouth County?
The federal record around Plymouth County runs heavier than most — 2,727 documented sites, mostly Brownfields entries (1,557), the nearest PFAS record under a tenth of a mile 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.
Everything above is measured at Plymouth County's scale — its 7a band and its 207-day season. Your yard writes its own version of Plymouth County's numbers: we read soil, sun, drainage and frost at your exact address. Try it for 14 days — no card required.
Will It Grow Here?
Zone fit is the first question — each answer below reads Massachusetts's frost window, season length, and soil profile against the plant's real requirements.
What this page reads at Plymouth County’s own scale
9 of the readings below were taken at Plymouth County's own scale — its own ~207-day span between 28°F freezes, the 3 most extensive soil series mapped here and 2,727 documented sites inside its boundary; one is borrowed from a wider read, named and linked below.
Measured here
- Plymouth County's own USDA hardiness band, zones 7aUSDA PHZM 2023
- Plymouth County's own 28°F hard-freeze dates and its ~207-day span between themNOAA 1991–2020 Climate Normals
- The soil order, drainage, surface pH, and the 3 most extensive named soil series mapped in Plymouth CountyUSDA NRCS SSURGO
- 2,727 documented contamination sites inside the county boundary, distance-sorted from its center — the closest PFAS record under a tenth of a mile outFederal environmental registers
- Plymouth County's boundary and the 421,453 acres inside itUS Census TIGER/Line 2025
- Which of 1,086 plants clear zones 7a and a ~207-day seasonGrowable Ground crop-matching engine
- The 2 ecoregions Plymouth County spans, Northeastern Coastal Zone the largestUS EPA Level III Ecoregions
- Open occurrence records documented in Plymouth County for 2 tracked speciesGBIF derived datasets (CC0 / CC BY 4.0)
- Which agricultural compounds go onto Plymouth County farmland, and roughly how muchUSGS NAWQA EPest county estimates
Inherited from a wider read
- The growing challenges every Massachusetts grower plans around — written at state scale, so they stay on the state guidefrom Massachusetts
What this page can’t tell you
- How the season shifts across Plymouth County — the ~207 days above is one reading at its centre; the 12 towns below each carry their owntowns in this county →
- The soil pH, drainage, sun hours, and frost pockets on any one lot among Plymouth County's 421,453 acreswhy one lot differs from the next →
- Which of those 2,727 documented sites actually reaches your soil — that needs your address, the wind, and the groundwater directionhow we read the record →
- Where cold air settles, which slopes face the sun, and which way the wind runs on your own ground — none of it survives being averaged over Plymouth Countyread your own land →