Data: 2023 USDA zones (PRISM/OSU) · NOAA 1991–2020 normals · updated Oct 29, 2026

Planting zone for 04055 — Naples, ME

ZIP code 04055 (Naples, Cumberland County) is in USDA zone 5a: the coldest winter night averages −20 to −15 °F. The median last spring frost is May 5 and the first fall frost October 5.

Where ZIP 04055 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.

Zone5a−20 to −15 °F

Coldest night−28.9 to −26.1 °C

Last frostMay 5

First frostOct 5

2012 zone5a

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 5a means →

Frost forecast — next 7 nights

live from the National Weather Service

Loading the forecast for Naples, ME…

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 Naples, ME

JanFebMarAprMayJunJulAugSepOctNovDec

Blue: frost possible · fading green: frost risk falling or rising (90% → 10%) · green: frost-free

Last spring frostMay 5median — 50% chance of a later frost

Safe for tender plantsMay 17only 10% chance of frost after

First fall frostOctober 5median — 10% chance by Sep 22

Growing season151 daysfrost-free, median

A hard freeze (28 °F) usually ends around April 25 and returns around October 19.

From the NOAA station Bridgton 3 Nw, ME — 9 miles away, elevation 509 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 04055

JanFebMarAprMayJunJulAugSepOctNovDec

PeasSow outdoors · Mar 24 – Apr 7

SpinachSow outdoors · Mar 24 – Apr 14

Broccoli, cabbageStart indoors · Feb 24 – Mar 10

Broccoli, cabbageTransplant · Apr 14 – Apr 28

Onion setsPlant outdoors · Apr 7 – Apr 21

PotatoesPlant outdoors · Apr 14 – Apr 28

LettuceSow outdoors · Apr 7 – Apr 21

Carrots, beetsSow outdoors · Apr 14 – Apr 28

TomatoesStart indoors · Mar 10 – Mar 24

TomatoesTransplant · May 12 – May 26

Peppers, eggplantStart indoors · Feb 24 – Mar 10

Peppers, eggplantTransplant · May 19 – Jun 2

BeansSow outdoors · May 12 – May 26

Sweet cornSow outdoors · May 12 – May 26

Cucumbers, squashSow outdoors · May 12 – May 26

Fall lettuce, spinachSow outdoors · Aug 10 – Aug 24

GarlicPlant cloves · Sep 21 – Oct 26

Start seeds indoorsSow or plant outdoorsFall plantingMedian last & first frost

Counted from the median last spring frost (May 5) and first fall frost (Oct 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 04055 came on Apr 16 — 6 days earlier than the 1991–2020 average (Apr 22).

average
Apr 222026
Apr 16

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 Naples, ME

The soil mapped at the center of ZIP 04055 is Peru — moderately decomposed plant material, moderately well drained.

TextureModerately decomposed plant materialtop layer

pH4.9strongly acidic; most vegetables like 6.0–7.0

DrainageModerately well drainednatural drainage class

Organic matter80%high

Hydrologic groupC/Dslow when drained; wet otherwise

Farmland classFarmland of local importanceUSDA classification

Map unit: Peru 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 04055; soils change within a few hundred feet, so a home soil test (pH, nutrients) is still the best guide.

Climate in Naples, ME

Summer high78 °Faverage high, July

Winter low7 °Faverage low, January

Hot days2days a year at 90 °F or more

Freezing nights177nights a year at 32 °F or less

Growing degree days1,946base 50 °F — the season’s usable heat

Longest day15 h 29 mindaylight on June 21

Shortest day8 h 53 mindaylight on December 21

Onions to growLong-daysummer days reach 15+ hours, enough for long-day varieties (intermediate types work too)

Precipitation50.2 inper year, rain and melted snow

Average high and low, by month

Precipitation by month inches

NOAA NCEI U.S. Climate Normals 1991–2020 — temperature: Bridgton 3 Nw, ME (9 mi away); precipitation: Sebago 2.4 Ese, ME (7 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.

South Casco, ME · 7 mi

040225a

Denmark, ME · 9 mi

040575a

North Bridgton, ME · 9 mi

040715b

Raymond, ME · 9 mi

040245a

East Baldwin, ME · 10 mi

Maine planting zones →

Questions about 04055

What planting zone is ZIP code 04055?

ZIP code 04055 (Naples, ME) is in USDA hardiness zone 5a on the 2023 map: the coldest night of an average winter reaches −20 to −15 °F (−28.9 to −26.1 °C).

When is the last frost in Naples, ME?

The median last spring frost (32 °F) near 04055 is May 5; after May 17 there is only a 10% chance of frost. Data: NOAA 1991–2020 normals, Bridgton 3 Nw station.

When is the first frost in Naples, ME?

The median first fall frost near 04055 is October 5, giving a median frost-free growing season of 151 days.

When should I plant tomatoes in 04055?

Start tomato seeds indoors around Mar 10 – Mar 24 and set transplants outside around May 12 – May 26, one to three weeks after the median last frost.

How much rain and snow does 04055 get?

About 50.2 inches of precipitation a year (NOAA 1991–2020 normals, Sebago 2.4 Ese station).

How hot do summers get in Naples, ME?

The average high peaks at 78 °F in July, with about 2 days a year at 90 °F or more.

What kind of soil does 04055 have?

The USDA soil survey maps Peru at the center of ZIP 04055: moderately decomposed plant material, moderately well drained, pH about 4.9 (strongly acidic).

Did spring come early in Naples, ME in 2026?

Spring leaf-out near 04055 came on Apr 16 in 2026, 6 days earlier than the 1991–2020 average (Apr 22), according to the USA National Phenology Network Spring Index.

What kind of onions grow in Naples, ME?

Long-day onions: the longest day near 04055 is 15 h 29 min, so summer days reach 15+ hours, enough for long-day varieties (intermediate types work too).