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

Planting zone for 01940 — Lynnfield, MA

ZIP code 01940 (Lynnfield, Essex County) is in USDA zone 6b: the coldest winter night averages −5 to 0 °F. The median last spring frost is May 3 and the first fall frost October 9.

Where ZIP 01940 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 3
First frostOct 9
2012 zone6b

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 6b means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Lynnfield, 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 Lynnfield, MA

JanFebMarAprMayJunJulAugSepOctNovDec
Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free
Last spring frostMay 3median — 50% chance of a later frost
Safe for tender plantsMay 20only 10% chance of frost after
First fall frostOctober 9median — 10% chance by Sep 29
Growing season157 daysfrost-free, median

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

From the NOAA station Middleton, MA — 4 miles away, elevation 112 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 01940

JanFebMarAprMayJunJulAugSepOctNovDec
PeasSow outdoors · Mar 22 – Apr 5
SpinachSow outdoors · Mar 22 – Apr 12
Broccoli, cabbageStart indoors · Feb 22 – Mar 8
Broccoli, cabbageTransplant · Apr 12 – Apr 26
Onion setsPlant outdoors · Apr 5 – Apr 19
PotatoesPlant outdoors · Apr 12 – Apr 26
LettuceSow outdoors · Apr 5 – Apr 19
Carrots, beetsSow outdoors · Apr 12 – Apr 26
TomatoesStart indoors · Mar 8 – Mar 22
TomatoesTransplant · May 10 – May 24
Peppers, eggplantStart indoors · Feb 22 – Mar 8
Peppers, eggplantTransplant · May 17 – May 31
BeansSow outdoors · May 10 – May 24
Sweet cornSow outdoors · May 10 – May 24
Cucumbers, squashSow outdoors · May 10 – May 24
Fall lettuce, spinachSow outdoors · Aug 14 – Aug 28
GarlicPlant cloves · Sep 25 – Oct 30
Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 3) and first fall frost (Oct 9) 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 01940 came on Apr 4 — 4 days earlier than the 1991–2020 average (Apr 8).

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 6b in Massachusetts

548 plants native to the lower 48 states, recorded in Massachusetts, and rated by the USDA to survive −5 °F or colder — the bottom of zone 6b. 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 188

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 159

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 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 Lynnfield, MA.

Soil in Lynnfield, MA

The soil mapped at the center of ZIP 01940 is Woodbridge — moderately decomposed plant material, moderately well drained.

TextureModerately decomposed plant materialtop layer
DrainageModerately well drainednatural drainage class
Organic matter95%high
Hydrologic groupC/Dslow when drained; wet otherwise
Farmland classFarmland of statewide importanceUSDA classification

Map unit: Woodbridge fine sandy loam, 0 to 8 percent slopes, very 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 01940; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Lynnfield, MA

Summer high81 °Faverage high, July
Winter low16 °Faverage low, January
Hot days16days a year at 90 °F or more
Freezing nights129nights a year at 32 °F or less
Growing degree days2,473base 50 °F — the season’s usable heat
Longest day15 h 18 mindaylight on June 21
Shortest day9 h 03 mindaylight on December 21
Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)
Precipitation48.1 inper year, rain and melted snow
Snowfall48 inper year

Average high and low, by month

10°20°30°40°50°60°70°80°90°32 °FJanuary: average high 35 °F, low 16 °F 35°16° JanFebruary: average high 38 °F, low 17 °F 38°17° FebMarch: average high 44 °F, low 25 °F 44°25° MarApril: average high 56 °F, low 35 °F 56°35° AprMay: average high 67 °F, low 45 °F 67°45° MayJune: average high 75 °F, low 55 °F 75°55° JunJuly: average high 81 °F, low 61 °F 81°61° JulAugust: average high 80 °F, low 59 °F 80°59° AugSeptember: average high 73 °F, low 52 °F 73°52° SepOctober: average high 62 °F, low 41 °F 62°41° OctNovember: average high 50 °F, low 31 °F 50°31° NovDecember: average high 40 °F, low 23 °F 40°23° Dec

Precipitation by month inches · ❄ = snowfall

0″1″2″3″4″5″January: 3.49 in precipitation, 13.4 in snowfall 3.5❄13 JanFebruary: 3.27 in precipitation, 13.2 in snowfall 3.3❄13 FebMarch: 4.54 in precipitation, 9.4 in snowfall 4.5❄9 MarApril: 4.35 in precipitation, 1.8 in snowfall 4.3❄2 AprMay: 3.73 in precipitation 3.7 MayJune: 4.25 in precipitation 4.3 JunJuly: 3.79 in precipitation 3.8 JulAugust: 3.32 in precipitation 3.3 AugSeptember: 3.84 in precipitation 3.8 SepOctober: 4.75 in precipitation 4.8 OctNovember: 4.00 in precipitation, 1.1 in snowfall 4.0❄1 NovDecember: 4.79 in precipitation, 8.9 in snowfall 4.8❄9 Dec

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Middleton, MA (4 mi away); precipitation: Middleton, MA (4 mi away). Daylight is calculated from latitude.

Nearby ZIP codes

All 8 nearest ZIP codes share zone 6b.

018806b
Wakefield, MA · 2 mi
018676b
Reading, MA · 3 mi
019606b
Peabody, MA · 4 mi
018646b
North Reading, MA · 4 mi
018896b
North Reading, MA · 4 mi
019046b
Lynn, MA · 5 mi
019376b
Hathorne, MA · 5 mi
019066b
Saugus, MA · 5 mi

Massachusetts planting zones →

Questions about 01940

What planting zone is ZIP code 01940?

ZIP code 01940 (Lynnfield, 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 Lynnfield, MA?

The median last spring frost (32 °F) near 01940 is May 3; after May 20 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Middleton station.

When is the first frost in Lynnfield, MA?

The median first fall frost near 01940 is October 9, giving a median frost-free growing season of 157 days.

When should I plant tomatoes in 01940?

Start tomato seeds indoors around Mar 8 – Mar 22 and set transplants outside around May 10 – May 24, one to three weeks after the median last frost.

How much rain and snow does 01940 get?

About 48.1 inches of precipitation a year and 48 inches of snowfall (NOAA 1991–2020 normals, Middleton station).

How hot do summers get in Lynnfield, MA?

The average high peaks at 81 °F in July, with about 16 days a year at 90 °F or more.

What kind of soil does 01940 have?

The USDA soil survey maps Woodbridge at the center of ZIP 01940: moderately decomposed plant material, moderately well drained.

Did spring come early in Lynnfield, MA in 2026?

Spring leaf-out near 01940 came on Apr 4 in 2026, 4 days earlier than the 1991–2020 average (Apr 8), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Lynnfield, MA?

Long-day onions: the longest day near 01940 is 15 h 18 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).