Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated

Planting zone for 02748 — South Dartmouth, MA

ZIP code 02748 (South Dartmouth, Bristol County) is in USDA zone 7a: the coldest winter night averages 0 to 5 °F. The median last spring frost is April 11 and the first fall frost November 5.

Where ZIP 02748 is

Outlined: the ZIP code area · tap the map for the zone at any spot · scroll or pinch to zoom

Not the official USDA Plant Hardiness Zone Map. Zones come from the 2023 USDA hardiness-zone data by the PRISM Group, Oregon State University; we re-mapped and recolored them. The official map is at planthardiness.ars.usda.gov.

Zone7a0 to 5 °F
Coldest night−17.8 to −15 °C
Last frostApr 11
First frostNov 5
2012 zone7a

Same zone as on the 2012 map. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 7a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for South Dartmouth, MA…

Forecast data: National Weather Service (api.weather.gov), public domain. This is not a warning service — for official frost and freeze warnings see weather.gov.

Frost dates in South Dartmouth, MA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 11median — 50% chance of a later frost
Safe for tender plantsApril 22only 10% chance of frost after
First fall frostNovember 5median — 10% chance by Oct 24
Growing season208 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 1 and returns around November 16.

From the NOAA station New Bedford Coop, MA — 4 miles away, elevation 20 ft. NOAA NCEI U.S. Climate Normals 1991–2020, 32 °F threshold. Low spots and valleys can freeze later in spring than the station.

When to plant vegetables in 02748

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Feb 28 – Mar 14
SpinachSow outdoors · Feb 28 – Mar 21
Broccoli, cabbageStart indoors · Jan 31 – Feb 14
Broccoli, cabbageTransplant · Mar 21 – Apr 4
Onion setsPlant outdoors · Mar 14 – Mar 28
PotatoesPlant outdoors · Mar 21 – Apr 4
LettuceSow outdoors · Mar 14 – Mar 28
Carrots, beetsSow outdoors · Mar 21 – Apr 4
TomatoesStart indoors · Feb 14 – Feb 28
TomatoesTransplant · Apr 18 – May 2
Peppers, eggplantStart indoors · Jan 31 – Feb 14
Peppers, eggplantTransplant · Apr 25 – May 9
BeansSow outdoors · Apr 18 – May 2
Sweet cornSow outdoors · Apr 18 – May 2
Cucumbers, squashSow outdoors · Apr 18 – May 2
Fall lettuce, spinachSow outdoors · Sep 10 – Sep 24
GarlicPlant cloves · Oct 22 – Nov 26
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 11) and first fall frost (Nov 5) with the rules of thumb U.S. extension services publish. Cool-season crops take a light frost; warm-season crops do best once the soil is above about 60 °F.

When spring arrived in 2026

In 2026, spring leaf-out near 02748 came on Apr 6 — 5 days later than the 1991–2020 average (Apr 1).

JanFebMarAprMayJun

The Spring Index marks the day when accumulated warmth is enough for lilac and honeysuckle to leaf out — a widely used signal that the growing season has started. Source: USA National Phenology Network, www.usanpn.org — Spring Indices, first leaf, 2026 (data as of 2026-09-08) and 30-year average 1991–2020 (CC BY 4.0).

Native plants for zone 7a in Massachusetts

561 plants native to the lower 48 states, recorded in Massachusetts, and rated by the USDA to survive 0 °F or colder — the bottom of zone 7a. Each links to its USDA PLANTS profile.

Trees 67

American basswood100 ft · blooms late spring · low shade tolerance · to −46 °FAmerican beech80 ft · blooms mid spring · low shade tolerance · to −44 °FAmerican chestnut115 ft · blooms early summer · high shade tolerance · to −33 °FAmerican elm120 ft · blooms early spring · medium shade tolerance · to −46 °FAmerican sycamore100 ft · blooms spring · medium shade tolerance · to −34 °Farborvitae50 ft · blooms mid spring · medium shade tolerance · to −33 °F

Shrubs 110

alderleaf buckthorn3 ft · blooms late spring · low shade tolerance · to −33 °FAllegheny serviceberry35 ft · blooms early spring · low shade tolerance · to −38 °Falternateleaf dogwood25 ft · blooms mid spring · low shade tolerance · to −47 °FAmerican black currant3 ft · blooms early spring · to −46 °FAmerican hazelnut10 ft · blooms spring · medium shade tolerance · to −33 °FAmerican holly40 ft · blooms mid spring · low shade tolerance · to −20 °F

Wildflowers & perennials 192

alkali buttercup1 ft · blooms late spring · low shade tolerance · to −38 °FAmerican bur-reed3 ft · blooms indeterminate · medium shade tolerance · to −33 °FAmerican eelgrass1 ft · blooms mid summer · high shade tolerance · to −33 °FAmerican licorice4 ft · blooms late spring · medium shade tolerance · to −38 °FAmerican lotus3 ft · blooms mid summer · high shade tolerance · to −36 °FAmerican pokeweed7 ft · blooms mid summer · low shade tolerance · to −33 °F

Grasses 165

American beachgrass2.5 ft · blooms spring · high shade tolerance · to −28 °FAmerican cupscale3 ft · blooms early summer · high shade tolerance · to −18 °Farctic brome3 ft · blooms early summer · low shade tolerance · to −33 °FAtlantic mannagrass3 ft · blooms summer · low shade tolerance · to −8 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °FBailey's sedge2.1 ft · blooms late spring · low shade tolerance · to −33 °F

Vines 9

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °FAmerican wisteria50 ft · blooms spring · low shade tolerance · to −3 °Fdevil's darning needles15 ft · blooms mid summer · medium shade tolerance · to −38 °Ffrost grape83 ft · blooms late spring · medium shade tolerance · to −23 °Friverbank grape45 ft · blooms late spring · medium shade tolerance · to −33 °Fsummer grape30 ft · blooms late spring · low shade tolerance · to −23 °F

Source: USDA, NRCS. 2026. The PLANTS Database (plants.usda.gov), National Plant Data Team — state distribution, native status and the “Temperature, Minimum” characteristic. Check light, moisture and soil needs before buying; local nurseries and your state native plant society can confirm what thrives in South Dartmouth, MA.

Soil in South Dartmouth, MA

The soil mapped at the center of ZIP 02748 is Whitman — peat, very poorly drained.

TexturePeattop layer
DrainageVery poorly drainedconsider raised beds
Organic matter95%high
Hydrologic groupDwater soaks in very slowly
Farmland classNot prime farmlandUSDA classification

Map unit: Whitman fine sandy loam, 0 to 3 percent slopes, extremely stony.

Soil Survey Staff, Natural Resources Conservation Service, USDA. Soil Survey Geographic (SSURGO) Database, via Soil Data Access, accessed 2026-10-29. The soil at the center point of ZIP 02748; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in South Dartmouth, MA

Summer high84 °Faverage high, July
Winter low22 °Faverage low, January
Hot days13days a year at 90 °F or more
Freezing nights104nights a year at 32 °F or less
Growing degree days3,235base 50 °F — the season’s usable heat
Longest day15 h 11 mindaylight on June 21
Shortest day9 h 10 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation48.7 inper year, rain and melted snow

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 38 °F, low 22 °F 38°22° JanFebruary: average high 40 °F, low 23 °F 40°23° FebMarch: average high 47 °F, low 29 °F 47°29° MarApril: average high 56 °F, low 40 °F 56°40° AprMay: average high 68 °F, low 50 °F 68°50° MayJune: average high 78 °F, low 60 °F 78°60° JunJuly: average high 84 °F, low 67 °F 84°67° JulAugust: average high 82 °F, low 66 °F 82°66° AugSeptember: average high 75 °F, low 59 °F 75°59° SepOctober: average high 64 °F, low 49 °F 64°49° OctNovember: average high 53 °F, low 37 °F 53°37° NovDecember: average high 43 °F, low 28 °F 43°28° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 4.12 in precipitation 4.1 JanFebruary: 3.66 in precipitation 3.7 FebMarch: 4.84 in precipitation 4.8 MarApril: 4.34 in precipitation 4.3 AprMay: 3.54 in precipitation 3.5 MayJune: 3.62 in precipitation 3.6 JunJuly: 3.05 in precipitation 3.0 JulAugust: 3.72 in precipitation 3.7 AugSeptember: 3.99 in precipitation 4.0 SepOctober: 4.60 in precipitation 4.6 OctNovember: 4.26 in precipitation 4.3 NovDecember: 4.98 in precipitation 5.0 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: New Bedford Coop, MA (4 mi away); precipitation: Dartmouth 2.5 Ssw, MA (3 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 7a.

027447a
New Bedford, MA · 5 mi
027417a
New Bedford, MA · 6 mi
027427a
New Bedford, MA · 6 mi
027917a
Westport Point, MA · 6 mi
027407a
New Bedford, MA · 6 mi
027907a
Westport, MA · 7 mi
027477a
North Dartmouth, MA · 8 mi
027197a
Fairhaven, MA · 8 mi

Massachusetts planting zones →

Questions about 02748

What planting zone is ZIP code 02748?

ZIP code 02748 (South Dartmouth, MA) is in USDA hardiness zone 7a on the 2023 map: the coldest night of an average winter reaches 0 to 5 °F (−17.8 to −15 °C).

When is the last frost in South Dartmouth, MA?

The median last spring frost (32 °F) near 02748 is April 11; after April 22 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, New Bedford Coop station.

When is the first frost in South Dartmouth, MA?

The median first fall frost near 02748 is November 5, giving a median frost-free growing season of 208 days.

When should I plant tomatoes in 02748?

Start tomato seeds indoors around Feb 14 – Feb 28 and set transplants outside around Apr 18 – May 2, one to three weeks after the median last frost.

How much rain and snow does 02748 get?

About 48.7 inches of precipitation a year (NOAA 1991–2020 normals, Dartmouth 2.5 Ssw station).

How hot do summers get in South Dartmouth, MA?

The average high peaks at 84 °F in July, with about 13 days a year at 90 °F or more.

What kind of soil does 02748 have?

The USDA soil survey maps Whitman at the center of ZIP 02748: peat, very poorly drained.

Did spring come early in South Dartmouth, MA in 2026?

Spring leaf-out near 02748 came on Apr 6 in 2026, 5 days later than the 1991–2020 average (Apr 1), according to the USA National Phenology Network Spring Index.

What kind of onions grow in South Dartmouth, MA?

Long-day onions: the longest day near 02748 is 15 h 11 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).