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

Planting zone for 01566 — Sturbridge, MA

ZIP code 01566 (Sturbridge, Worcester County) is in USDA zone 6a: the coldest winter night averages −10 to −5 °F. The median last spring frost is April 28 and the first fall frost October 15.

Where ZIP 01566 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.

Zone6a−10 to −5 °F
Coldest night−23.3 to −20.6 °C
Last frostApr 28
First frostOct 15
2012 zone6a

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 6a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Sturbridge, 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 Sturbridge, MA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostApril 28median — 50% chance of a later frost
Safe for tender plantsMay 17only 10% chance of frost after
First fall frostOctober 15median — 10% chance by Oct 1
Growing season169 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 13 and returns around October 27.

From the NOAA station E Brimfield Lake, MA — 2 miles away, elevation 699 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 01566

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 17 – Mar 31
SpinachSow outdoors · Mar 17 – Apr 7
Broccoli, cabbageStart indoors · Feb 17 – Mar 3
Broccoli, cabbageTransplant · Apr 7 – Apr 21
Onion setsPlant outdoors · Mar 31 – Apr 14
PotatoesPlant outdoors · Apr 7 – Apr 21
LettuceSow outdoors · Mar 31 – Apr 14
Carrots, beetsSow outdoors · Apr 7 – Apr 21
TomatoesStart indoors · Mar 3 – Mar 17
TomatoesTransplant · May 5 – May 19
Peppers, eggplantStart indoors · Feb 17 – Mar 3
Peppers, eggplantTransplant · May 12 – May 26
BeansSow outdoors · May 5 – May 19
Sweet cornSow outdoors · May 5 – May 19
Cucumbers, squashSow outdoors · May 5 – May 19
Fall lettuce, spinachSow outdoors · Aug 20 – Sep 3
GarlicPlant cloves · Oct 1 – Nov 5
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (Apr 28) and first fall frost (Oct 15) 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 01566 came on Apr 8 — 5 days earlier than the 1991–2020 average (Apr 13).

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 6a in Massachusetts

544 plants native to the lower 48 states, recorded in Massachusetts, and rated by the USDA to survive −10 °F or colder — the bottom of zone 6a. Each links to its USDA PLANTS profile.

Trees 66

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 109

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 186

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 157

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 °Fawlfruit sedge4 ft · blooms mid spring · low shade tolerance · to −38 °FBailey's sedge2.1 ft · blooms late spring · low shade tolerance · to −33 °Fbeaked spikerush3 ft · blooms late spring · high shade tolerance · to −28 °F

Vines 8

American bittersweet15 ft · blooms spring · low shade tolerance · to −38 °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 °Ftrumpet creeper2 ft · blooms summer · high shade tolerance · to −13 °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 Sturbridge, MA.

Soil in Sturbridge, MA

The soil mapped at the center of ZIP 01566 is Windsor — moderately decomposed plant material, excessively drained.

TextureModerately decomposed plant materialtop layer
DrainageExcessively drainednatural drainage class
Organic matter95%high
Hydrologic groupAwater soaks in fast
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Windsor loamy sand, 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 01566; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Sturbridge, MA

Summer high81 °Faverage high, July
Winter low16 °Faverage low, January
Hot days5days a year at 90 °F or more
Freezing nights150nights a year at 32 °F or less
Growing degree days2,517base 50 °F — the season’s usable heat
Longest day15 h 15 mindaylight on June 21
Shortest day9 h 06 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation48.6 inper year, rain and melted snow
Snowfall64 inper year; 64 days with snow on the ground

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 34 °F, low 16 °F 34°16° JanFebruary: average high 37 °F, low 17 °F 37°17° FebMarch: average high 44 °F, low 25 °F 44°25° MarApril: average high 57 °F, low 36 °F 57°36° AprMay: average high 68 °F, low 46 °F 68°46° MayJune: average high 75 °F, low 56 °F 75°56° JunJuly: average high 81 °F, low 62 °F 81°62° JulAugust: average high 79 °F, low 60 °F 79°60° AugSeptember: average high 72 °F, low 52 °F 72°52° SepOctober: average high 61 °F, low 40 °F 61°40° OctNovember: average high 50 °F, low 31 °F 50°31° NovDecember: average high 39 °F, low 23 °F 39°23° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 3.67 in precipitation, 13.4 in snowfall 3.7❄13 JanFebruary: 3.19 in precipitation, 16.8 in snowfall 3.2❄17 FebMarch: 4.26 in precipitation, 13.6 in snowfall 4.3❄14 MarApril: 4.32 in precipitation, 3.8 in snowfall 4.3❄4 AprMay: 3.48 in precipitation 3.5 MayJune: 3.86 in precipitation 3.9 JunJuly: 4.04 in precipitation 4.0 JulAugust: 4.41 in precipitation 4.4 AugSeptember: 4.07 in precipitation 4.1 SepOctober: 4.85 in precipitation, 0.1 in snowfall 4.8 OctNovember: 3.91 in precipitation, 2 in snowfall 3.9❄2 NovDecember: 4.56 in precipitation, 13.8 in snowfall 4.6❄14 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: E Brimfield Lake, MA (2 mi away); precipitation: E Brimfield Lake, MA (2 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

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

015186a
Fiskdale, MA · 2 mi
015506b
Southbridge, MA · 4 mi
015086a
Charlton City, MA · 6 mi
015066a
Brookfield, MA · 6 mi
015076b
Charlton, MA · 6 mi
015216a
Holland, MA · 6 mi
010106a
Brimfield, MA · 7 mi
015096b
Charlton Depot, MA · 7 mi

Massachusetts planting zones →

Questions about 01566

What planting zone is ZIP code 01566?

ZIP code 01566 (Sturbridge, MA) is in USDA hardiness zone 6a on the 2023 map: the coldest night of an average winter reaches −10 to −5 °F (−23.3 to −20.6 °C).

When is the last frost in Sturbridge, MA?

The median last spring frost (32 °F) near 01566 is April 28; after May 17 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, E Brimfield Lake station.

When is the first frost in Sturbridge, MA?

The median first fall frost near 01566 is October 15, giving a median frost-free growing season of 169 days.

When should I plant tomatoes in 01566?

Start tomato seeds indoors around Mar 3 – Mar 17 and set transplants outside around May 5 – May 19, one to three weeks after the median last frost.

How much rain and snow does 01566 get?

About 48.6 inches of precipitation a year and 64 inches of snowfall (NOAA 1991–2020 normals, E Brimfield Lake station).

How hot do summers get in Sturbridge, MA?

The average high peaks at 81 °F in July, with about 5 days a year at 90 °F or more.

What kind of soil does 01566 have?

The USDA soil survey maps Windsor at the center of ZIP 01566: moderately decomposed plant material, excessively drained.

Did spring come early in Sturbridge, MA in 2026?

Spring leaf-out near 01566 came on Apr 8 in 2026, 5 days earlier than the 1991–2020 average (Apr 13), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Sturbridge, MA?

Long-day onions: the longest day near 01566 is 15 h 15 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).