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

Planting zone for 01503 — Berlin, MA

ZIP code 01503 (Berlin, Worcester County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is May 2 and the first fall frost October 6.

Where ZIP 01503 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.

Zone6b−5 to 0 °F
Coldest night−20.6 to −17.8 °C
Last frostMay 2
First frostOct 6
2012 zone6a

Was 6a on the 2012 map — half a zone warmer now. The zone is the one at the center of the ZIP code; hilly ZIPs can span two zones. What zone 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Berlin, 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 Berlin, MA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 2median — 50% chance of a later frost
Safe for tender plantsMay 16only 10% chance of frost after
First fall frostOctober 6median — 10% chance by Sep 25
Growing season156 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 21 and returns around October 18.

From the NOAA station Maynard 2, MA — 10 miles away, elevation 207 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 01503

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 21 – Apr 4
SpinachSow outdoors · Mar 21 – Apr 11
Broccoli, cabbageStart indoors · Feb 21 – Mar 7
Broccoli, cabbageTransplant · Apr 11 – Apr 25
Onion setsPlant outdoors · Apr 4 – Apr 18
PotatoesPlant outdoors · Apr 11 – Apr 25
LettuceSow outdoors · Apr 4 – Apr 18
Carrots, beetsSow outdoors · Apr 11 – Apr 25
TomatoesStart indoors · Mar 7 – Mar 21
TomatoesTransplant · May 9 – May 23
Peppers, eggplantStart indoors · Feb 21 – Mar 7
Peppers, eggplantTransplant · May 16 – May 30
BeansSow outdoors · May 9 – May 23
Sweet cornSow outdoors · May 9 – May 23
Cucumbers, squashSow outdoors · May 9 – May 23
Fall lettuce, spinachSow outdoors · Aug 11 – Aug 25
GarlicPlant cloves · Sep 22 – Oct 27
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 2) and first fall frost (Oct 6) 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 01503 came on Apr 8 — about the same time as the 1991–2020 average (Apr 9).

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).

Soil in Berlin, MA

The soil mapped at the center of ZIP 01503 is Canton — fine sandy loam, well drained.

TextureFine sandy loamdrains and warms fast; dries out and needs more feeding
pH4.3strongly acidic; most vegetables like 6.0–7.0
DrainageWell drainednatural drainage class
Organic matter5.75%high
Hydrologic groupBwater soaks in moderately
Farmland classprime farmlandUSDA classification

Map unit: Canton fine sandy loam, 3 to 8 percent slopes.

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 01503; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Berlin, MA

Summer high87 °Faverage high, July
Winter low15 °Faverage low, January
Hot days22days a year at 90 °F or more
Freezing nights147nights a year at 32 °F or less
Growing degree days2,872base 50 °F — the season’s usable heat
Longest day15 h 17 mindaylight on June 21
Shortest day9 h 04 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation48.8 inper year, rain and melted snow

Average high and low, by month

0°10°20°30°40°50°60°70°80°90°100°32 °FJanuary: average high 37 °F, low 15 °F 37°15° JanFebruary: average high 41 °F, low 16 °F 41°16° FebMarch: average high 49 °F, low 24 °F 49°24° MarApril: average high 62 °F, low 34 °F 62°34° AprMay: average high 73 °F, low 45 °F 73°45° MayJune: average high 81 °F, low 55 °F 81°55° JunJuly: average high 87 °F, low 60 °F 87°60° JulAugust: average high 85 °F, low 58 °F 85°58° AugSeptember: average high 78 °F, low 49 °F 78°49° SepOctober: average high 66 °F, low 38 °F 66°38° OctNovember: average high 54 °F, low 29 °F 54°29° NovDecember: average high 43 °F, low 21 °F 43°21° Dec

Precipitation by month inches

0″1″2″3″4″5″January: 3.52 in precipitation 3.5 JanFebruary: 3.24 in precipitation 3.2 FebMarch: 4.17 in precipitation 4.2 MarApril: 4.41 in precipitation 4.4 AprMay: 3.70 in precipitation 3.7 MayJune: 4.27 in precipitation 4.3 JunJuly: 3.80 in precipitation 3.8 JulAugust: 4.06 in precipitation 4.1 AugSeptember: 4.02 in precipitation 4.0 SepOctober: 4.90 in precipitation 4.9 OctNovember: 4.10 in precipitation 4.1 NovDecember: 4.57 in precipitation 4.6 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Maynard 2, MA (10 mi away); precipitation: Berlin 1.3 Wsw, MA (within 1 mile). Daylight is calculated from latitude.

Nearby ZIP codes

2 of the 8 nearest ZIP codes are in a different zone — elevation and distance from water change winter lows quickly.

015106a
Clinton, MA · 3 mi
017406b
Bolton, MA · 4 mi
015326b
Northborough, MA · 4 mi
017496b
Hudson, MA · 5 mi
015056a
Boylston, MA · 5 mi
015616b
South Lancaster, MA · 5 mi
017526b
Marlborough, MA · 5 mi
017756b
Stow, MA · 7 mi

Massachusetts planting zones →

Questions about 01503

What planting zone is ZIP code 01503?

ZIP code 01503 (Berlin, MA) is in USDA hardiness zone 6b on the 2023 map: the coldest night of an average winter reaches −5 to 0 °F (−20.6 to −17.8 °C).

When is the last frost in Berlin, MA?

The median last spring frost (32 °F) near 01503 is May 2; after May 16 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Maynard 2 station.

When is the first frost in Berlin, MA?

The median first fall frost near 01503 is October 6, giving a median frost-free growing season of 156 days.

When should I plant tomatoes in 01503?

Start tomato seeds indoors around Mar 7 – Mar 21 and set transplants outside around May 9 – May 23, one to three weeks after the median last frost.

How much rain and snow does 01503 get?

About 48.8 inches of precipitation a year (NOAA 1991–2020 normals, Berlin 1.3 Wsw station).

How hot do summers get in Berlin, MA?

The average high peaks at 87 °F in July, with about 22 days a year at 90 °F or more.

What kind of soil does 01503 have?

The USDA soil survey maps Canton at the center of ZIP 01503: fine sandy loam, well drained, pH about 4.3 (strongly acidic).

Did spring come early in Berlin, MA in 2026?

Spring leaf-out near 01503 came on Apr 8 in 2026, about the same as the 1991–2020 average (Apr 9), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Berlin, MA?

Long-day onions: the longest day near 01503 is 15 h 17 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).

Did the zone for 01503 change?

Yes. The 2012 USDA map put 01503 in zone 6a; the 2023 map puts it in zone 6b. The newer map uses 1991–2020 data and more weather stations.